Merged from the latest developing branch.

[MacVim.git] / src / ex_cmds.c

/* vi:set ts=8 sts=4 sw=4:
 *
 * VIM - Vi IMproved    by Bram Moolenaar
 *
 * Do ":help uganda"  in Vim to read copying and usage conditions.
 * Do ":help credits" in Vim to see a list of people who contributed.
 * See README.txt for an overview of the Vim source code.
 */

/*
 * ex_cmds.c: some functions for command line commands
 */

#if defined(MSDOS) || defined(WIN16) || defined(WIN32) || defined(_WIN64)
# include "vimio.h"     /* for mch_open(), must be before vim.h */
#endif

#include "vim.h"
#include "version.h"

#ifdef FEAT_EX_EXTRA
static int linelen __ARGS((int *has_tab));
#endif
static void do_filter __ARGS((linenr_T line1, linenr_T line2, exarg_T *eap, char_u *cmd, int do_in, int do_out));
#ifdef FEAT_VIMINFO
static char_u *viminfo_filename __ARGS((char_u  *));
static void do_viminfo __ARGS((FILE *fp_in, FILE *fp_out, int want_info, int want_marks, int force_read));
static int viminfo_encoding __ARGS((vir_T *virp));
static int read_viminfo_up_to_marks __ARGS((vir_T *virp, int forceit, int writing));
#endif

static int check_overwrite __ARGS((exarg_T *eap, buf_T *buf, char_u *fname, char_u *ffname, int other));
static int check_readonly __ARGS((int *forceit, buf_T *buf));
#ifdef FEAT_AUTOCMD
static void delbuf_msg __ARGS((char_u *name));
#endif
static int
#ifdef __BORLANDC__
    _RTLENTRYF
#endif
        help_compare __ARGS((const void *s1, const void *s2));

/*
 * ":ascii" and "ga".
 */
/*ARGSUSED*/
    void
do_ascii(eap)
    exarg_T     *eap;
{
    int         c;
    char        buf1[20];
    char        buf2[20];
    char_u      buf3[7];
#ifdef FEAT_MBYTE
    int         cc[MAX_MCO];
    int         ci = 0;
    int         len;

    if (enc_utf8)
        c = utfc_ptr2char(ml_get_cursor(), cc);
    else
#endif
        c = gchar_cursor();
    if (c == NUL)
    {
        MSG("NUL");
        return;
    }

#ifdef FEAT_MBYTE
    IObuff[0] = NUL;
    if (!has_mbyte || (enc_dbcs != 0 && c < 0x100) || c < 0x80)
#endif
    {
        if (c == NL)        /* NUL is stored as NL */
            c = NUL;
        if (vim_isprintc_strict(c) && (c < ' '
#ifndef EBCDIC
                    || c > '~'
#endif
                               ))
        {
            transchar_nonprint(buf3, c);
            sprintf(buf1, "  <%s>", (char *)buf3);
        }
        else
            buf1[0] = NUL;
#ifndef EBCDIC
        if (c >= 0x80)
            sprintf(buf2, "  <M-%s>", transchar(c & 0x7f));
        else
#endif
            buf2[0] = NUL;
        vim_snprintf((char *)IObuff, IOSIZE,
                _("<%s>%s%s  %d,  Hex %02x,  Octal %03o"),
                                           transchar(c), buf1, buf2, c, c, c);
#ifdef FEAT_MBYTE
        if (enc_utf8)
            c = cc[ci++];
        else
            c = 0;
#endif
    }

#ifdef FEAT_MBYTE
    /* Repeat for combining characters. */
    while (has_mbyte && (c >= 0x100 || (enc_utf8 && c >= 0x80)))
    {
        len = (int)STRLEN(IObuff);
        /* This assumes every multi-byte char is printable... */
        if (len > 0)
            IObuff[len++] = ' ';
        IObuff[len++] = '<';
        if (enc_utf8 && utf_iscomposing(c)
# ifdef USE_GUI
                && !gui.in_use
# endif
                )
            IObuff[len++] = ' '; /* draw composing char on top of a space */
        len += (*mb_char2bytes)(c, IObuff + len);
        vim_snprintf((char *)IObuff + len, IOSIZE - len,
                        c < 0x10000 ? _("> %d, Hex %04x, Octal %o")
                                    : _("> %d, Hex %08x, Octal %o"), c, c, c);
        if (ci == MAX_MCO)
            break;
        if (enc_utf8)
            c = cc[ci++];
        else
            c = 0;
    }
#endif

    msg(IObuff);
}

#if defined(FEAT_EX_EXTRA) || defined(PROTO)
/*
 * ":left", ":center" and ":right": align text.
 */
    void
ex_align(eap)
    exarg_T     *eap;
{
    pos_T       save_curpos;
    int         len;
    int         indent = 0;
    int         new_indent;
    int         has_tab;
    int         width;

#ifdef FEAT_RIGHTLEFT
    if (curwin->w_p_rl)
    {
        /* switch left and right aligning */
        if (eap->cmdidx == CMD_right)
            eap->cmdidx = CMD_left;
        else if (eap->cmdidx == CMD_left)
            eap->cmdidx = CMD_right;
    }
#endif

    width = atoi((char *)eap->arg);
    save_curpos = curwin->w_cursor;
    if (eap->cmdidx == CMD_left)    /* width is used for new indent */
    {
        if (width >= 0)
            indent = width;
    }
    else
    {
        /*
         * if 'textwidth' set, use it
         * else if 'wrapmargin' set, use it
         * if invalid value, use 80
         */
        if (width <= 0)
            width = curbuf->b_p_tw;
        if (width == 0 && curbuf->b_p_wm > 0)
            width = W_WIDTH(curwin) - curbuf->b_p_wm;
        if (width <= 0)
            width = 80;
    }

    if (u_save((linenr_T)(eap->line1 - 1), (linenr_T)(eap->line2 + 1)) == FAIL)
        return;

    for (curwin->w_cursor.lnum = eap->line1;
                 curwin->w_cursor.lnum <= eap->line2; ++curwin->w_cursor.lnum)
    {
        if (eap->cmdidx == CMD_left)            /* left align */
            new_indent = indent;
        else
        {
            has_tab = FALSE;    /* avoid uninit warnings */
            len = linelen(eap->cmdidx == CMD_right ? &has_tab
                                                   : NULL) - get_indent();

            if (len <= 0)                       /* skip blank lines */
                continue;

            if (eap->cmdidx == CMD_center)
                new_indent = (width - len) / 2;
            else
            {
                new_indent = width - len;       /* right align */

                /*
                 * Make sure that embedded TABs don't make the text go too far
                 * to the right.
                 */
                if (has_tab)
                    while (new_indent > 0)
                    {
                        (void)set_indent(new_indent, 0);
                        if (linelen(NULL) <= width)
                        {
                            /*
                             * Now try to move the line as much as possible to
                             * the right.  Stop when it moves too far.
                             */
                            do
                                (void)set_indent(++new_indent, 0);
                            while (linelen(NULL) <= width);
                            --new_indent;
                            break;
                        }
                        --new_indent;
                    }
            }
        }
        if (new_indent < 0)
            new_indent = 0;
        (void)set_indent(new_indent, 0);                /* set indent */
    }
    changed_lines(eap->line1, 0, eap->line2 + 1, 0L);
    curwin->w_cursor = save_curpos;
    beginline(BL_WHITE | BL_FIX);
}

/*
 * Get the length of the current line, excluding trailing white space.
 */
    static int
linelen(has_tab)
    int     *has_tab;
{
    char_u  *line;
    char_u  *first;
    char_u  *last;
    int     save;
    int     len;

    /* find the first non-blank character */
    line = ml_get_curline();
    first = skipwhite(line);

    /* find the character after the last non-blank character */
    for (last = first + STRLEN(first);
                                last > first && vim_iswhite(last[-1]); --last)
        ;
    save = *last;
    *last = NUL;
    len = linetabsize(line);            /* get line length */
    if (has_tab != NULL)                /* check for embedded TAB */
        *has_tab = (vim_strrchr(first, TAB) != NULL);
    *last = save;

    return len;
}

/* Buffer for two lines used during sorting.  They are allocated to
 * contain the longest line being sorted. */
static char_u   *sortbuf1;
static char_u   *sortbuf2;

static int      sort_ic;                /* ignore case */
static int      sort_nr;                /* sort on number */
static int      sort_rx;                /* sort on regex instead of skipping it */

static int      sort_abort;             /* flag to indicate if sorting has been interrupted */

/* Struct to store info to be sorted. */
typedef struct
{
    linenr_T    lnum;                   /* line number */
    long        start_col_nr;           /* starting column number or number */
    long        end_col_nr;             /* ending column number */
} sorti_T;

static int
#ifdef __BORLANDC__
_RTLENTRYF
#endif
sort_compare __ARGS((const void *s1, const void *s2));

    static int
#ifdef __BORLANDC__
_RTLENTRYF
#endif
sort_compare(s1, s2)
    const void  *s1;
    const void  *s2;
{
    sorti_T     l1 = *(sorti_T *)s1;
    sorti_T     l2 = *(sorti_T *)s2;
    int         result = 0;

    /* If the user interrupts, there's no way to stop qsort() immediately, but
     * if we return 0 every time, qsort will assume it's done sorting and
     * exit. */
    if (sort_abort)
        return 0;
    fast_breakcheck();
    if (got_int)
        sort_abort = TRUE;

    /* When sorting numbers "start_col_nr" is the number, not the column
     * number. */
    if (sort_nr)
        result = l1.start_col_nr - l2.start_col_nr;
    else
    {
        /* We need to copy one line into "sortbuf1", because there is no
         * guarantee that the first pointer becomes invalid when obtaining the
         * second one. */
        STRNCPY(sortbuf1, ml_get(l1.lnum) + l1.start_col_nr,
                                         l1.end_col_nr - l1.start_col_nr + 1);
        sortbuf1[l1.end_col_nr - l1.start_col_nr] = 0;
        STRNCPY(sortbuf2, ml_get(l2.lnum) + l2.start_col_nr,
                                         l2.end_col_nr - l2.start_col_nr + 1);
        sortbuf2[l2.end_col_nr - l2.start_col_nr] = 0;

        result = sort_ic ? STRICMP(sortbuf1, sortbuf2)
                                                 : STRCMP(sortbuf1, sortbuf2);
    }

    /* If two lines have the same value, preserve the original line order. */
    if (result == 0)
        return (int)(l1.lnum - l2.lnum);
    return result;
}

/*
 * ":sort".
 */
    void
ex_sort(eap)
    exarg_T     *eap;
{
    regmatch_T  regmatch;
    int         len;
    linenr_T    lnum;
    long        maxlen = 0;
    sorti_T     *nrs;
    size_t      count = eap->line2 - eap->line1 + 1;
    size_t      i;
    char_u      *p;
    char_u      *s;
    char_u      *s2;
    char_u      c;                      /* temporary character storage */
    int         unique = FALSE;
    long        deleted;
    colnr_T     start_col;
    colnr_T     end_col;
    int         sort_oct;               /* sort on octal number */
    int         sort_hex;               /* sort on hex number */

    /* Sorting one line is really quick! */
    if (count <= 1)
        return;

    if (u_save((linenr_T)(eap->line1 - 1), (linenr_T)(eap->line2 + 1)) == FAIL)
        return;
    sortbuf1 = NULL;
    sortbuf2 = NULL;
    regmatch.regprog = NULL;
    nrs = (sorti_T *)lalloc((long_u)(count * sizeof(sorti_T)), TRUE);
    if (nrs == NULL)
        goto sortend;

    sort_abort = sort_ic = sort_rx = sort_nr = sort_oct = sort_hex = 0;

    for (p = eap->arg; *p != NUL; ++p)
    {
        if (vim_iswhite(*p))
            ;
        else if (*p == 'i')
            sort_ic = TRUE;
        else if (*p == 'r')
            sort_rx = TRUE;
        else if (*p == 'n')
            sort_nr = 2;
        else if (*p == 'o')
            sort_oct = 2;
        else if (*p == 'x')
            sort_hex = 2;
        else if (*p == 'u')
            unique = TRUE;
        else if (*p == '"')     /* comment start */
            break;
        else if (check_nextcmd(p) != NULL)
        {
            eap->nextcmd = check_nextcmd(p);
            break;
        }
        else if (!ASCII_ISALPHA(*p) && regmatch.regprog == NULL)
        {
            s = skip_regexp(p + 1, *p, TRUE, NULL);
            if (*s != *p)
            {
                EMSG(_(e_invalpat));
                goto sortend;
            }
            *s = NUL;
            /* Use last search pattern if sort pattern is empty. */
            if (s == p + 1 && last_search_pat() != NULL)
                regmatch.regprog = vim_regcomp(last_search_pat(), RE_MAGIC);
            else
                regmatch.regprog = vim_regcomp(p + 1, RE_MAGIC);
            if (regmatch.regprog == NULL)
                goto sortend;
            p = s;              /* continue after the regexp */
            regmatch.rm_ic = p_ic;
        }
        else
        {
            EMSG2(_(e_invarg2), p);
            goto sortend;
        }
    }

    /* Can only have one of 'n', 'o' and 'x'. */
    if (sort_nr + sort_oct + sort_hex > 2)
    {
        EMSG(_(e_invarg));
        goto sortend;
    }

    /* From here on "sort_nr" is used as a flag for any number sorting. */
    sort_nr += sort_oct + sort_hex;

    /*
     * Make an array with all line numbers.  This avoids having to copy all
     * the lines into allocated memory.
     * When sorting on strings "start_col_nr" is the offset in the line, for
     * numbers sorting it's the number to sort on.  This means the pattern
     * matching and number conversion only has to be done once per line.
     * Also get the longest line length for allocating "sortbuf".
     */
    for (lnum = eap->line1; lnum <= eap->line2; ++lnum)
    {
        s = ml_get(lnum);
        len = (int)STRLEN(s);
        if (maxlen < len)
            maxlen = len;

        start_col = 0;
        end_col = len;
        if (regmatch.regprog != NULL && vim_regexec(&regmatch, s, 0))
        {
            if (sort_rx)
            {
                start_col = (colnr_T)(regmatch.startp[0] - s);
                end_col = (colnr_T)(regmatch.endp[0] - s);
            }
            else
                start_col = (colnr_T)(regmatch.endp[0] - s);
        }
        else
            if (regmatch.regprog != NULL)
                end_col = 0;

        if (sort_nr)
        {
            /* Make sure vim_str2nr doesn't read any digits past the end
             * of the match, by temporarily terminating the string there */
            s2 = s + end_col;
            c = *s2;
            (*s2) = 0;
            /* Sorting on number: Store the number itself. */
            p = s + start_col;
            if (sort_hex)
                s = skiptohex(p);
            else
                s = skiptodigit(p);
            if (s > p && s[-1] == '-')
                --s;  /* include preceding negative sign */
            vim_str2nr(s, NULL, NULL, sort_oct, sort_hex,
                                        &nrs[lnum - eap->line1].start_col_nr, NULL);
            (*s2) = c;
        }
        else
        {
            /* Store the column to sort at. */
            nrs[lnum - eap->line1].start_col_nr = start_col;
            nrs[lnum - eap->line1].end_col_nr = end_col;
        }

        nrs[lnum - eap->line1].lnum = lnum;

        if (regmatch.regprog != NULL)
            fast_breakcheck();
        if (got_int)
            goto sortend;
    }

    /* Allocate a buffer that can hold the longest line. */
    sortbuf1 = alloc((unsigned)maxlen + 1);
    if (sortbuf1 == NULL)
        goto sortend;
    sortbuf2 = alloc((unsigned)maxlen + 1);
    if (sortbuf2 == NULL)
        goto sortend;

    /* Sort the array of line numbers.  Note: can't be interrupted! */
    qsort((void *)nrs, count, sizeof(sorti_T), sort_compare);

    if (sort_abort)
        goto sortend;

    /* Insert the lines in the sorted order below the last one. */
    lnum = eap->line2;
    for (i = 0; i < count; ++i)
    {
        s = ml_get(nrs[eap->forceit ? count - i - 1 : i].lnum);
        if (!unique || i == 0
                || (sort_ic ? STRICMP(s, sortbuf1) : STRCMP(s, sortbuf1)) != 0)
        {
            if (ml_append(lnum++, s, (colnr_T)0, FALSE) == FAIL)
                break;
            if (unique)
                STRCPY(sortbuf1, s);
        }
        fast_breakcheck();
        if (got_int)
            goto sortend;
    }

    /* delete the original lines if appending worked */
    if (i == count)
        for (i = 0; i < count; ++i)
            ml_delete(eap->line1, FALSE);
    else
        count = 0;

    /* Adjust marks for deleted (or added) lines and prepare for displaying. */
    deleted = (long)(count - (lnum - eap->line2));
    if (deleted > 0)
        mark_adjust(eap->line2 - deleted, eap->line2, (long)MAXLNUM, -deleted);
    else if (deleted < 0)
        mark_adjust(eap->line2, MAXLNUM, -deleted, 0L);
    changed_lines(eap->line1, 0, eap->line2 + 1, -deleted);

    curwin->w_cursor.lnum = eap->line1;
    beginline(BL_WHITE | BL_FIX);

sortend:
    vim_free(nrs);
    vim_free(sortbuf1);
    vim_free(sortbuf2);
    vim_free(regmatch.regprog);
    if (got_int)
        EMSG(_(e_interr));
}

/*
 * ":retab".
 */
    void
ex_retab(eap)
    exarg_T     *eap;
{
    linenr_T    lnum;
    int         got_tab = FALSE;
    long        num_spaces = 0;
    long        num_tabs;
    long        len;
    long        col;
    long        vcol;
    long        start_col = 0;          /* For start of white-space string */
    long        start_vcol = 0;         /* For start of white-space string */
    int         temp;
    long        old_len;
    char_u      *ptr;
    char_u      *new_line = (char_u *)1;    /* init to non-NULL */
    int         did_undo;               /* called u_save for current line */
    int         new_ts;
    int         save_list;
    linenr_T    first_line = 0;         /* first changed line */
    linenr_T    last_line = 0;          /* last changed line */

    save_list = curwin->w_p_list;
    curwin->w_p_list = 0;           /* don't want list mode here */

    new_ts = getdigits(&(eap->arg));
    if (new_ts < 0)
    {
        EMSG(_(e_positive));
        return;
    }
    if (new_ts == 0)
        new_ts = curbuf->b_p_ts;
    for (lnum = eap->line1; !got_int && lnum <= eap->line2; ++lnum)
    {
        ptr = ml_get(lnum);
        col = 0;
        vcol = 0;
        did_undo = FALSE;
        for (;;)
        {
            if (vim_iswhite(ptr[col]))
            {
                if (!got_tab && num_spaces == 0)
                {
                    /* First consecutive white-space */
                    start_vcol = vcol;
                    start_col = col;
                }
                if (ptr[col] == ' ')
                    num_spaces++;
                else
                    got_tab = TRUE;
            }
            else
            {
                if (got_tab || (eap->forceit && num_spaces > 1))
                {
                    /* Retabulate this string of white-space */

                    /* len is virtual length of white string */
                    len = num_spaces = vcol - start_vcol;
                    num_tabs = 0;
                    if (!curbuf->b_p_et)
                    {
                        temp = new_ts - (start_vcol % new_ts);
                        if (num_spaces >= temp)
                        {
                            num_spaces -= temp;
                            num_tabs++;
                        }
                        num_tabs += num_spaces / new_ts;
                        num_spaces -= (num_spaces / new_ts) * new_ts;
                    }
                    if (curbuf->b_p_et || got_tab ||
                                        (num_spaces + num_tabs < len))
                    {
                        if (did_undo == FALSE)
                        {
                            did_undo = TRUE;
                            if (u_save((linenr_T)(lnum - 1),
                                                (linenr_T)(lnum + 1)) == FAIL)
                            {
                                new_line = NULL;        /* flag out-of-memory */
                                break;
                            }
                        }

                        /* len is actual number of white characters used */
                        len = num_spaces + num_tabs;
                        old_len = (long)STRLEN(ptr);
                        new_line = lalloc(old_len - col + start_col + len + 1,
                                                                        TRUE);
                        if (new_line == NULL)
                            break;
                        if (start_col > 0)
                            mch_memmove(new_line, ptr, (size_t)start_col);
                        mch_memmove(new_line + start_col + len,
                                      ptr + col, (size_t)(old_len - col + 1));
                        ptr = new_line + start_col;
                        for (col = 0; col < len; col++)
                            ptr[col] = (col < num_tabs) ? '\t' : ' ';
                        ml_replace(lnum, new_line, FALSE);
                        if (first_line == 0)
                            first_line = lnum;
                        last_line = lnum;
                        ptr = new_line;
                        col = start_col + len;
                    }
                }
                got_tab = FALSE;
                num_spaces = 0;
            }
            if (ptr[col] == NUL)
                break;
            vcol += chartabsize(ptr + col, (colnr_T)vcol);
#ifdef FEAT_MBYTE
            if (has_mbyte)
                col += (*mb_ptr2len)(ptr + col);
            else
#endif
                ++col;
        }
        if (new_line == NULL)               /* out of memory */
            break;
        line_breakcheck();
    }
    if (got_int)
        EMSG(_(e_interr));

    if (curbuf->b_p_ts != new_ts)
        redraw_curbuf_later(NOT_VALID);
    if (first_line != 0)
        changed_lines(first_line, 0, last_line + 1, 0L);

    curwin->w_p_list = save_list;       /* restore 'list' */

    curbuf->b_p_ts = new_ts;
    coladvance(curwin->w_curswant);

    u_clearline();
}
#endif

/*
 * :move command - move lines line1-line2 to line dest
 *
 * return FAIL for failure, OK otherwise
 */
    int
do_move(line1, line2, dest)
    linenr_T    line1;
    linenr_T    line2;
    linenr_T    dest;
{
    char_u      *str;
    linenr_T    l;
    linenr_T    extra;      /* Num lines added before line1 */
    linenr_T    num_lines;  /* Num lines moved */
    linenr_T    last_line;  /* Last line in file after adding new text */

    if (dest >= line1 && dest < line2)
    {
        EMSG(_("E134: Move lines into themselves"));
        return FAIL;
    }

    num_lines = line2 - line1 + 1;

    /*
     * First we copy the old text to its new location -- webb
     * Also copy the flag that ":global" command uses.
     */
    if (u_save(dest, dest + 1) == FAIL)
        return FAIL;
    for (extra = 0, l = line1; l <= line2; l++)
    {
        str = vim_strsave(ml_get(l + extra));
        if (str != NULL)
        {
            ml_append(dest + l - line1, str, (colnr_T)0, FALSE);
            vim_free(str);
            if (dest < line1)
                extra++;
        }
    }

    /*
     * Now we must be careful adjusting our marks so that we don't overlap our
     * mark_adjust() calls.
     *
     * We adjust the marks within the old text so that they refer to the
     * last lines of the file (temporarily), because we know no other marks
     * will be set there since these line numbers did not exist until we added
     * our new lines.
     *
     * Then we adjust the marks on lines between the old and new text positions
     * (either forwards or backwards).
     *
     * And Finally we adjust the marks we put at the end of the file back to
     * their final destination at the new text position -- webb
     */
    last_line = curbuf->b_ml.ml_line_count;
    mark_adjust(line1, line2, last_line - line2, 0L);
    if (dest >= line2)
    {
        mark_adjust(line2 + 1, dest, -num_lines, 0L);
        curbuf->b_op_start.lnum = dest - num_lines + 1;
        curbuf->b_op_end.lnum = dest;
    }
    else
    {
        mark_adjust(dest + 1, line1 - 1, num_lines, 0L);
        curbuf->b_op_start.lnum = dest + 1;
        curbuf->b_op_end.lnum = dest + num_lines;
    }
    curbuf->b_op_start.col = curbuf->b_op_end.col = 0;
    mark_adjust(last_line - num_lines + 1, last_line,
                                             -(last_line - dest - extra), 0L);

    /*
     * Now we delete the original text -- webb
     */
    if (u_save(line1 + extra - 1, line2 + extra + 1) == FAIL)
        return FAIL;

    for (l = line1; l <= line2; l++)
        ml_delete(line1 + extra, TRUE);

    if (!global_busy && num_lines > p_report)
    {
        if (num_lines == 1)
            MSG(_("1 line moved"));
        else
            smsg((char_u *)_("%ld lines moved"), num_lines);
    }

    /*
     * Leave the cursor on the last of the moved lines.
     */
    if (dest >= line1)
        curwin->w_cursor.lnum = dest;
    else
        curwin->w_cursor.lnum = dest + (line2 - line1) + 1;

    if (line1 < dest)
        changed_lines(line1, 0, dest + num_lines + 1, 0L);
    else
        changed_lines(dest + 1, 0, line1 + num_lines, 0L);

    return OK;
}

/*
 * ":copy"
 */
    void
ex_copy(line1, line2, n)
    linenr_T    line1;
    linenr_T    line2;
    linenr_T    n;
{
    linenr_T    count;
    char_u      *p;

    count = line2 - line1 + 1;
    curbuf->b_op_start.lnum = n + 1;
    curbuf->b_op_end.lnum = n + count;
    curbuf->b_op_start.col = curbuf->b_op_end.col = 0;

    /*
     * there are three situations:
     * 1. destination is above line1
     * 2. destination is between line1 and line2
     * 3. destination is below line2
     *
     * n = destination (when starting)
     * curwin->w_cursor.lnum = destination (while copying)
     * line1 = start of source (while copying)
     * line2 = end of source (while copying)
     */
    if (u_save(n, n + 1) == FAIL)
        return;

    curwin->w_cursor.lnum = n;
    while (line1 <= line2)
    {
        /* need to use vim_strsave() because the line will be unlocked within
         * ml_append() */
        p = vim_strsave(ml_get(line1));
        if (p != NULL)
        {
            ml_append(curwin->w_cursor.lnum, p, (colnr_T)0, FALSE);
            vim_free(p);
        }
        /* situation 2: skip already copied lines */
        if (line1 == n)
            line1 = curwin->w_cursor.lnum;
        ++line1;
        if (curwin->w_cursor.lnum < line1)
            ++line1;
        if (curwin->w_cursor.lnum < line2)
            ++line2;
        ++curwin->w_cursor.lnum;
    }

    appended_lines_mark(n, count);

    msgmore((long)count);
}

static char_u   *prevcmd = NULL;        /* the previous command */

#if defined(EXITFREE) || defined(PROTO)
    void
free_prev_shellcmd()
{
    vim_free(prevcmd);
}
#endif

/*
 * Handle the ":!cmd" command.  Also for ":r !cmd" and ":w !cmd"
 * Bangs in the argument are replaced with the previously entered command.
 * Remember the argument.
 *
 * RISCOS: Bangs only replaced when followed by a space, since many
 * pathnames contain one.
 */
    void
do_bang(addr_count, eap, forceit, do_in, do_out)
    int         addr_count;
    exarg_T     *eap;
    int         forceit;
    int         do_in, do_out;
{
    char_u              *arg = eap->arg;        /* command */
    linenr_T            line1 = eap->line1;     /* start of range */
    linenr_T            line2 = eap->line2;     /* end of range */
    char_u              *newcmd = NULL;         /* the new command */
    int                 free_newcmd = FALSE;    /* need to free() newcmd */
    int                 ins_prevcmd;
    char_u              *t;
    char_u              *p;
    char_u              *trailarg;
    int                 len;
    int                 scroll_save = msg_scroll;

    /*
     * Disallow shell commands for "rvim".
     * Disallow shell commands from .exrc and .vimrc in current directory for
     * security reasons.
     */
    if (check_restricted() || check_secure())
        return;

    if (addr_count == 0)                /* :! */
    {
        msg_scroll = FALSE;         /* don't scroll here */
        autowrite_all();
        msg_scroll = scroll_save;
    }

    /*
     * Try to find an embedded bang, like in :!<cmd> ! [args]
     * (:!! is indicated by the 'forceit' variable)
     */
    ins_prevcmd = forceit;
    trailarg = arg;
    do
    {
        len = (int)STRLEN(trailarg) + 1;
        if (newcmd != NULL)
            len += (int)STRLEN(newcmd);
        if (ins_prevcmd)
        {
            if (prevcmd == NULL)
            {
                EMSG(_(e_noprev));
                vim_free(newcmd);
                return;
            }
            len += (int)STRLEN(prevcmd);
        }
        if ((t = alloc(len)) == NULL)
        {
            vim_free(newcmd);
            return;
        }
        *t = NUL;
        if (newcmd != NULL)
            STRCAT(t, newcmd);
        if (ins_prevcmd)
            STRCAT(t, prevcmd);
        p = t + STRLEN(t);
        STRCAT(t, trailarg);
        vim_free(newcmd);
        newcmd = t;

        /*
         * Scan the rest of the argument for '!', which is replaced by the
         * previous command.  "\!" is replaced by "!" (this is vi compatible).
         */
        trailarg = NULL;
        while (*p)
        {
            if (*p == '!'
#ifdef RISCOS
                        && (p[1] == ' ' || p[1] == NUL)
#endif
                                        )
            {
                if (p > newcmd && p[-1] == '\\')
                    STRMOVE(p - 1, p);
                else
                {
                    trailarg = p;
                    *trailarg++ = NUL;
                    ins_prevcmd = TRUE;
                    break;
                }
            }
            ++p;
        }
    } while (trailarg != NULL);

    vim_free(prevcmd);
    prevcmd = newcmd;

    if (bangredo)           /* put cmd in redo buffer for ! command */
    {
        AppendToRedobuffLit(prevcmd, -1);
        AppendToRedobuff((char_u *)"\n");
        bangredo = FALSE;
    }
    /*
     * Add quotes around the command, for shells that need them.
     */
    if (*p_shq != NUL)
    {
        newcmd = alloc((unsigned)(STRLEN(prevcmd) + 2 * STRLEN(p_shq) + 1));
        if (newcmd == NULL)
            return;
        STRCPY(newcmd, p_shq);
        STRCAT(newcmd, prevcmd);
        STRCAT(newcmd, p_shq);
        free_newcmd = TRUE;
    }
    if (addr_count == 0)                /* :! */
    {
        /* echo the command */
        msg_start();
        msg_putchar(':');
        msg_putchar('!');
        msg_outtrans(newcmd);
        msg_clr_eos();
        windgoto(msg_row, msg_col);

        do_shell(newcmd, 0);
    }
    else                                /* :range! */
    {
        /* Careful: This may recursively call do_bang() again! (because of
         * autocommands) */
        do_filter(line1, line2, eap, newcmd, do_in, do_out);
#ifdef FEAT_AUTOCMD
        apply_autocmds(EVENT_SHELLFILTERPOST, NULL, NULL, FALSE, curbuf);
#endif
    }
    if (free_newcmd)
        vim_free(newcmd);
}

/*
 * do_filter: filter lines through a command given by the user
 *
 * We mostly use temp files and the call_shell() routine here. This would
 * normally be done using pipes on a UNIX machine, but this is more portable
 * to non-unix machines. The call_shell() routine needs to be able
 * to deal with redirection somehow, and should handle things like looking
 * at the PATH env. variable, and adding reasonable extensions to the
 * command name given by the user. All reasonable versions of call_shell()
 * do this.
 * Alternatively, if on Unix and redirecting input or output, but not both,
 * and the 'shelltemp' option isn't set, use pipes.
 * We use input redirection if do_in is TRUE.
 * We use output redirection if do_out is TRUE.
 */
    static void
do_filter(line1, line2, eap, cmd, do_in, do_out)
    linenr_T    line1, line2;
    exarg_T     *eap;           /* for forced 'ff' and 'fenc' */
    char_u      *cmd;
    int         do_in, do_out;
{
    char_u      *itmp = NULL;
    char_u      *otmp = NULL;
    linenr_T    linecount;
    linenr_T    read_linecount;
    pos_T       cursor_save;
    char_u      *cmd_buf;
#ifdef FEAT_AUTOCMD
    buf_T       *old_curbuf = curbuf;
#endif
    int         shell_flags = 0;

    if (*cmd == NUL)        /* no filter command */
        return;

#ifdef WIN3264
    /*
     * Check if external commands are allowed now.
     */
    if (can_end_termcap_mode(TRUE) == FALSE)
        return;
#endif

    cursor_save = curwin->w_cursor;
    linecount = line2 - line1 + 1;
    curwin->w_cursor.lnum = line1;
    curwin->w_cursor.col = 0;
    changed_line_abv_curs();
    invalidate_botline();

    /*
     * When using temp files:
     * 1. * Form temp file names
     * 2. * Write the lines to a temp file
     * 3.   Run the filter command on the temp file
     * 4. * Read the output of the command into the buffer
     * 5. * Delete the original lines to be filtered
     * 6. * Remove the temp files
     *
     * When writing the input with a pipe or when catching the output with a
     * pipe only need to do 3.
     */

    if (do_out)
        shell_flags |= SHELL_DOOUT;

#if !defined(USE_SYSTEM) && defined(UNIX)
    if (!do_in && do_out && !p_stmp)
    {
        /* Use a pipe to fetch stdout of the command, do not use a temp file. */
        shell_flags |= SHELL_READ;
        curwin->w_cursor.lnum = line2;
    }
    else if (do_in && !do_out && !p_stmp)
    {
        /* Use a pipe to write stdin of the command, do not use a temp file. */
        shell_flags |= SHELL_WRITE;
        curbuf->b_op_start.lnum = line1;
        curbuf->b_op_end.lnum = line2;
    }
    else if (do_in && do_out && !p_stmp)
    {
        /* Use a pipe to write stdin and fetch stdout of the command, do not
         * use a temp file. */
        shell_flags |= SHELL_READ|SHELL_WRITE;
        curbuf->b_op_start.lnum = line1;
        curbuf->b_op_end.lnum = line2;
        curwin->w_cursor.lnum = line2;
    }
    else
#endif
        if ((do_in && (itmp = vim_tempname('i')) == NULL)
                || (do_out && (otmp = vim_tempname('o')) == NULL))
        {
            EMSG(_(e_notmp));
            goto filterend;
        }

/*
 * The writing and reading of temp files will not be shown.
 * Vi also doesn't do this and the messages are not very informative.
 */
    ++no_wait_return;           /* don't call wait_return() while busy */
    if (itmp != NULL && buf_write(curbuf, itmp, NULL, line1, line2, eap,
                                           FALSE, FALSE, FALSE, TRUE) == FAIL)
    {
        msg_putchar('\n');              /* keep message from buf_write() */
        --no_wait_return;
#if defined(FEAT_AUTOCMD) && defined(FEAT_EVAL)
        if (!aborting())
#endif
            (void)EMSG2(_(e_notcreate), itmp);  /* will call wait_return */
        goto filterend;
    }
#ifdef FEAT_AUTOCMD
    if (curbuf != old_curbuf)
        goto filterend;
#endif

    if (!do_out)
        msg_putchar('\n');

    /* Create the shell command in allocated memory. */
    cmd_buf = make_filter_cmd(cmd, itmp, otmp);
    if (cmd_buf == NULL)
        goto filterend;

    windgoto((int)Rows - 1, 0);
    cursor_on();

    /*
     * When not redirecting the output the command can write anything to the
     * screen. If 'shellredir' is equal to ">", screen may be messed up by
     * stderr output of external command. Clear the screen later.
     * If do_in is FALSE, this could be something like ":r !cat", which may
     * also mess up the screen, clear it later.
     */
    if (!do_out || STRCMP(p_srr, ">") == 0 || !do_in)
        redraw_later_clear();

    if (do_out)
    {
        if (u_save((linenr_T)(line2), (linenr_T)(line2 + 1)) == FAIL)
        {
            vim_free(cmd_buf);
            goto error;
        }
        redraw_curbuf_later(VALID);
    }
    read_linecount = curbuf->b_ml.ml_line_count;

    /*
     * When call_shell() fails wait_return() is called to give the user a
     * chance to read the error messages. Otherwise errors are ignored, so you
     * can see the error messages from the command that appear on stdout; use
     * 'u' to fix the text
     * Switch to cooked mode when not redirecting stdin, avoids that something
     * like ":r !cat" hangs.
     * Pass on the SHELL_DOOUT flag when the output is being redirected.
     */
    if (call_shell(cmd_buf, SHELL_FILTER | SHELL_COOKED | shell_flags))
    {
        redraw_later_clear();
        wait_return(FALSE);
    }
    vim_free(cmd_buf);

    did_check_timestamps = FALSE;
    need_check_timestamps = TRUE;

    /* When interrupting the shell command, it may still have produced some
     * useful output.  Reset got_int here, so that readfile() won't cancel
     * reading. */
    ui_breakcheck();
    got_int = FALSE;

    if (do_out)
    {
        if (otmp != NULL)
        {
            if (readfile(otmp, NULL, line2, (linenr_T)0, (linenr_T)MAXLNUM,
                                                    eap, READ_FILTER) == FAIL)
            {
#if defined(FEAT_AUTOCMD) && defined(FEAT_EVAL)
                if (!aborting())
#endif
                {
                    msg_putchar('\n');
                    EMSG2(_(e_notread), otmp);
                }
                goto error;
            }
#ifdef FEAT_AUTOCMD
            if (curbuf != old_curbuf)
                goto filterend;
#endif
        }

        read_linecount = curbuf->b_ml.ml_line_count - read_linecount;

        if (shell_flags & SHELL_READ)
        {
            curbuf->b_op_start.lnum = line2 + 1;
            curbuf->b_op_end.lnum = curwin->w_cursor.lnum;
            appended_lines_mark(line2, read_linecount);
        }

        if (do_in)
        {
            if (cmdmod.keepmarks || vim_strchr(p_cpo, CPO_REMMARK) == NULL)
            {
                if (read_linecount >= linecount)
                    /* move all marks from old lines to new lines */
                    mark_adjust(line1, line2, linecount, 0L);
                else
                {
                    /* move marks from old lines to new lines, delete marks
                     * that are in deleted lines */
                    mark_adjust(line1, line1 + read_linecount - 1,
                                                                linecount, 0L);
                    mark_adjust(line1 + read_linecount, line2, MAXLNUM, 0L);
                }
            }

            /*
             * Put cursor on first filtered line for ":range!cmd".
             * Adjust '[ and '] (set by buf_write()).
             */
            curwin->w_cursor.lnum = line1;
            del_lines(linecount, TRUE);
            curbuf->b_op_start.lnum -= linecount;       /* adjust '[ */
            curbuf->b_op_end.lnum -= linecount;         /* adjust '] */
            write_lnum_adjust(-linecount);              /* adjust last line
                                                           for next write */
#ifdef FEAT_FOLDING
            foldUpdate(curwin, curbuf->b_op_start.lnum, curbuf->b_op_end.lnum);
#endif
        }
        else
        {
            /*
             * Put cursor on last new line for ":r !cmd".
             */
            linecount = curbuf->b_op_end.lnum - curbuf->b_op_start.lnum + 1;
            curwin->w_cursor.lnum = curbuf->b_op_end.lnum;
        }

        beginline(BL_WHITE | BL_FIX);       /* cursor on first non-blank */
        --no_wait_return;

        if (linecount > p_report)
        {
            if (do_in)
            {
                vim_snprintf((char *)msg_buf, sizeof(msg_buf),
                                    _("%ld lines filtered"), (long)linecount);
                if (msg(msg_buf) && !msg_scroll)
                    /* save message to display it after redraw */
                    set_keep_msg(msg_buf, 0);
            }
            else
                msgmore((long)linecount);
        }
    }
    else
    {
error:
        /* put cursor back in same position for ":w !cmd" */
        curwin->w_cursor = cursor_save;
        --no_wait_return;
        wait_return(FALSE);
    }

filterend:

#ifdef FEAT_AUTOCMD
    if (curbuf != old_curbuf)
    {
        --no_wait_return;
        EMSG(_("E135: *Filter* Autocommands must not change current buffer"));
    }
#endif
    if (itmp != NULL)
        mch_remove(itmp);
    if (otmp != NULL)
        mch_remove(otmp);
    vim_free(itmp);
    vim_free(otmp);
}

/*
 * Call a shell to execute a command.
 * When "cmd" is NULL start an interactive shell.
 */
    void
do_shell(cmd, flags)
    char_u      *cmd;
    int         flags;  /* may be SHELL_DOOUT when output is redirected */
{
    buf_T       *buf;
#ifndef FEAT_GUI_MSWIN
    int         save_nwr;
#endif
#ifdef MSWIN
    int         winstart = FALSE;
#endif

    /*
     * Disallow shell commands for "rvim".
     * Disallow shell commands from .exrc and .vimrc in current directory for
     * security reasons.
     */
    if (check_restricted() || check_secure())
    {
        msg_end();
        return;
    }

#ifdef MSWIN
    /*
     * Check if external commands are allowed now.
     */
    if (can_end_termcap_mode(TRUE) == FALSE)
        return;

    /*
     * Check if ":!start" is used.
     */
    if (cmd != NULL)
        winstart = (STRNICMP(cmd, "start ", 6) == 0);
#endif

    /*
     * For autocommands we want to get the output on the current screen, to
     * avoid having to type return below.
     */
    msg_putchar('\r');                  /* put cursor at start of line */
#ifdef FEAT_AUTOCMD
    if (!autocmd_busy)
#endif
    {
#ifdef MSWIN
        if (!winstart)
#endif
            stoptermcap();
    }
#ifdef MSWIN
    if (!winstart)
#endif
        msg_putchar('\n');              /* may shift screen one line up */

    /* warning message before calling the shell */
    if (p_warn
#ifdef FEAT_AUTOCMD
                && !autocmd_busy
#endif
                && msg_silent == 0)
        for (buf = firstbuf; buf; buf = buf->b_next)
            if (bufIsChanged(buf))
            {
#ifdef FEAT_GUI_MSWIN
                if (!winstart)
                    starttermcap();     /* don't want a message box here */
#endif
                MSG_PUTS(_("[No write since last change]\n"));
#ifdef FEAT_GUI_MSWIN
                if (!winstart)
                    stoptermcap();
#endif
                break;
            }

    /* This windgoto is required for when the '\n' resulted in a "delete line
     * 1" command to the terminal. */
    if (!swapping_screen())
        windgoto(msg_row, msg_col);
    cursor_on();
    (void)call_shell(cmd, SHELL_COOKED | flags);
    did_check_timestamps = FALSE;
    need_check_timestamps = TRUE;

    /*
     * put the message cursor at the end of the screen, avoids wait_return()
     * to overwrite the text that the external command showed
     */
    if (!swapping_screen())
    {
        msg_row = Rows - 1;
        msg_col = 0;
    }

#ifdef FEAT_AUTOCMD
    if (autocmd_busy)
    {
        if (msg_silent == 0)
            redraw_later_clear();
    }
    else
#endif
    {
        /*
         * For ":sh" there is no need to call wait_return(), just redraw.
         * Also for the Win32 GUI (the output is in a console window).
         * Otherwise there is probably text on the screen that the user wants
         * to read before redrawing, so call wait_return().
         */
#ifndef FEAT_GUI_MSWIN
        if (cmd == NULL
# ifdef WIN3264
                || (winstart && !need_wait_return)
# endif
           )
        {
            if (msg_silent == 0)
                redraw_later_clear();
            need_wait_return = FALSE;
        }
        else
        {
            /*
             * If we switch screens when starttermcap() is called, we really
             * want to wait for "hit return to continue".
             */
            save_nwr = no_wait_return;
            if (swapping_screen())
                no_wait_return = FALSE;
# ifdef AMIGA
            wait_return(term_console ? -1 : msg_silent == 0);   /* see below */
# else
            wait_return(msg_silent == 0);
# endif
            no_wait_return = save_nwr;
        }
#endif /* FEAT_GUI_W32 */

#ifdef MSWIN
        if (!winstart) /* if winstart==TRUE, never stopped termcap! */
#endif
            starttermcap();     /* start termcap if not done by wait_return() */

        /*
         * In an Amiga window redrawing is caused by asking the window size.
         * If we got an interrupt this will not work. The chance that the
         * window size is wrong is very small, but we need to redraw the
         * screen.  Don't do this if ':' hit in wait_return().  THIS IS UGLY
         * but it saves an extra redraw.
         */
#ifdef AMIGA
        if (skip_redraw)                /* ':' hit in wait_return() */
        {
            if (msg_silent == 0)
                redraw_later_clear();
        }
        else if (term_console)
        {
            OUT_STR(IF_EB("\033[0 q", ESC_STR "[0 q")); /* get window size */
            if (got_int && msg_silent == 0)
                redraw_later_clear();   /* if got_int is TRUE, redraw needed */
            else
                must_redraw = 0;        /* no extra redraw needed */
        }
#endif
    }

    /* display any error messages now */
    display_errors();

#ifdef FEAT_AUTOCMD
    apply_autocmds(EVENT_SHELLCMDPOST, NULL, NULL, FALSE, curbuf);
#endif
}

/*
 * Create a shell command from a command string, input redirection file and
 * output redirection file.
 * Returns an allocated string with the shell command, or NULL for failure.
 */
    char_u *
make_filter_cmd(cmd, itmp, otmp)
    char_u      *cmd;           /* command */
    char_u      *itmp;          /* NULL or name of input file */
    char_u      *otmp;          /* NULL or name of output file */
{
    char_u      *buf;
    long_u      len;

    len = (long_u)STRLEN(cmd) + 3;                      /* "()" + NUL */
    if (itmp != NULL)
        len += (long_u)STRLEN(itmp) + 9;                /* " { < " + " } " */
    if (otmp != NULL)
        len += (long_u)STRLEN(otmp) + (long_u)STRLEN(p_srr) + 2; /* "  " */
    buf = lalloc(len, TRUE);
    if (buf == NULL)
        return NULL;

#if (defined(UNIX) && !defined(ARCHIE)) || defined(OS2)
    /*
     * Put braces around the command (for concatenated commands) when
     * redirecting input and/or output.
     */
    if (itmp != NULL || otmp != NULL)
        sprintf((char *)buf, "(%s)", (char *)cmd);
    else
        STRCPY(buf, cmd);
    if (itmp != NULL)
    {
        STRCAT(buf, " < ");
        STRCAT(buf, itmp);
    }
#else
    /*
     * for shells that don't understand braces around commands, at least allow
     * the use of commands in a pipe.
     */
    STRCPY(buf, cmd);
    if (itmp != NULL)
    {
        char_u  *p;

        /*
         * If there is a pipe, we have to put the '<' in front of it.
         * Don't do this when 'shellquote' is not empty, otherwise the
         * redirection would be inside the quotes.
         */
        if (*p_shq == NUL)
        {
            p = vim_strchr(buf, '|');
            if (p != NULL)
                *p = NUL;
        }
# ifdef RISCOS
        STRCAT(buf, " { < ");   /* Use RISC OS notation for input. */
        STRCAT(buf, itmp);
        STRCAT(buf, " } ");
# else
        STRCAT(buf, " <");      /* " < " causes problems on Amiga */
        STRCAT(buf, itmp);
# endif
        if (*p_shq == NUL)
        {
            p = vim_strchr(cmd, '|');
            if (p != NULL)
            {
                STRCAT(buf, " ");   /* insert a space before the '|' for DOS */
                STRCAT(buf, p);
            }
        }
    }
#endif
    if (otmp != NULL)
        append_redir(buf, p_srr, otmp);

    return buf;
}

/*
 * Append output redirection for file "fname" to the end of string buffer "buf"
 * Works with the 'shellredir' and 'shellpipe' options.
 * The caller should make sure that there is enough room:
 *      STRLEN(opt) + STRLEN(fname) + 3
 */
    void
append_redir(buf, opt, fname)
    char_u      *buf;
    char_u      *opt;
    char_u      *fname;
{
    char_u      *p;

    buf += STRLEN(buf);
    /* find "%s", skipping "%%" */
    for (p = opt; (p = vim_strchr(p, '%')) != NULL; ++p)
        if (p[1] == 's')
            break;
    if (p != NULL)
    {
        *buf = ' '; /* not really needed? Not with sh, ksh or bash */
        sprintf((char *)buf + 1, (char *)opt, (char *)fname);
    }
    else
        sprintf((char *)buf,
#ifdef FEAT_QUICKFIX
# ifndef RISCOS
                opt != p_sp ? " %s%s" :
# endif
                " %s %s",
#else
# ifndef RISCOS
                " %s%s",        /* " > %s" causes problems on Amiga */
# else
                " %s %s",       /* But is needed for 'shellpipe' and RISC OS */
# endif
#endif
                (char *)opt, (char *)fname);
}

#ifdef FEAT_VIMINFO

static int no_viminfo __ARGS((void));
static int  viminfo_errcnt;

    static int
no_viminfo()
{
    /* "vim -i NONE" does not read or write a viminfo file */
    return (use_viminfo != NULL && STRCMP(use_viminfo, "NONE") == 0);
}

/*
 * Report an error for reading a viminfo file.
 * Count the number of errors.  When there are more than 10, return TRUE.
 */
    int
viminfo_error(errnum, message, line)
    char    *errnum;
    char    *message;
    char_u  *line;
{
    vim_snprintf((char *)IObuff, IOSIZE, _("%sviminfo: %s in line: "),
                                                             errnum, message);
    STRNCAT(IObuff, line, IOSIZE - STRLEN(IObuff) - 1);
    if (IObuff[STRLEN(IObuff) - 1] == '\n')
        IObuff[STRLEN(IObuff) - 1] = NUL;
    emsg(IObuff);
    if (++viminfo_errcnt >= 10)
    {
        EMSG(_("E136: viminfo: Too many errors, skipping rest of file"));
        return TRUE;
    }
    return FALSE;
}

/*
 * read_viminfo() -- Read the viminfo file.  Registers etc. which are already
 * set are not over-written unless force is TRUE. -- webb
 */
    int
read_viminfo(file, want_info, want_marks, forceit)
    char_u      *file;
    int         want_info;
    int         want_marks;
    int         forceit;
{
    FILE        *fp;
    char_u      *fname;

    if (no_viminfo())
        return FAIL;

    fname = viminfo_filename(file);         /* may set to default if NULL */
    if (fname == NULL)
        return FAIL;
    fp = mch_fopen((char *)fname, READBIN);

    if (p_verbose > 0)
    {
        verbose_enter();
        smsg((char_u *)_("Reading viminfo file \"%s\"%s%s%s"),
                fname,
                want_info ? _(" info") : "",
                want_marks ? _(" marks") : "",
                fp == NULL ? _(" FAILED") : "");
        verbose_leave();
    }

    vim_free(fname);
    if (fp == NULL)
        return FAIL;

    viminfo_errcnt = 0;
    do_viminfo(fp, NULL, want_info, want_marks, forceit);

    fclose(fp);

    return OK;
}

/*
 * write_viminfo() -- Write the viminfo file.  The old one is read in first so
 * that effectively a merge of current info and old info is done.  This allows
 * multiple vims to run simultaneously, without losing any marks etc.  If
 * forceit is TRUE, then the old file is not read in, and only internal info is
 * written to the file. -- webb
 */
    void
write_viminfo(file, forceit)
    char_u      *file;
    int         forceit;
{
    char_u      *fname;
    FILE        *fp_in = NULL;  /* input viminfo file, if any */
    FILE        *fp_out = NULL; /* output viminfo file */
    char_u      *tempname = NULL;       /* name of temp viminfo file */
    struct stat st_new;         /* mch_stat() of potential new file */
    char_u      *wp;
#if defined(UNIX) || defined(VMS)
    mode_t      umask_save;
#endif
#ifdef UNIX
    int         shortname = FALSE;      /* use 8.3 file name */
    struct stat st_old;         /* mch_stat() of existing viminfo file */
#endif
#ifdef WIN3264
    long        perm = -1;
#endif

    if (no_viminfo())
        return;

    fname = viminfo_filename(file);     /* may set to default if NULL */
    if (fname == NULL)
        return;

    fp_in = mch_fopen((char *)fname, READBIN);
    if (fp_in == NULL)
    {
        /* if it does exist, but we can't read it, don't try writing */
        if (mch_stat((char *)fname, &st_new) == 0)
            goto end;
#if defined(UNIX) || defined(VMS)
        /*
         * For Unix we create the .viminfo non-accessible for others,
         * because it may contain text from non-accessible documents.
         */
        umask_save = umask(077);
#endif
        fp_out = mch_fopen((char *)fname, WRITEBIN);
#if defined(UNIX) || defined(VMS)
        (void)umask(umask_save);
#endif
    }
    else
    {
        /*
         * There is an existing viminfo file.  Create a temporary file to
         * write the new viminfo into, in the same directory as the
         * existing viminfo file, which will be renamed later.
         */
#ifdef UNIX
        /*
         * For Unix we check the owner of the file.  It's not very nice to
         * overwrite a user's viminfo file after a "su root", with a
         * viminfo file that the user can't read.
         */
        st_old.st_dev = 0;
        st_old.st_ino = 0;
        st_old.st_mode = 0600;
        if (mch_stat((char *)fname, &st_old) == 0
                && getuid() != ROOT_UID
                && !(st_old.st_uid == getuid()
                        ? (st_old.st_mode & 0200)
                        : (st_old.st_gid == getgid()
                                ? (st_old.st_mode & 0020)
                                : (st_old.st_mode & 0002))))
        {
            int tt = msg_didany;

            /* avoid a wait_return for this message, it's annoying */
            EMSG2(_("E137: Viminfo file is not writable: %s"), fname);
            msg_didany = tt;
            fclose(fp_in);
            goto end;
        }
#endif
#ifdef WIN3264
        /* Get the file attributes of the existing viminfo file. */
        perm = mch_getperm(fname);
#endif

        /*
         * Make tempname.
         * May try twice: Once normal and once with shortname set, just in
         * case somebody puts his viminfo file in an 8.3 filesystem.
         */
        for (;;)
        {
            tempname = buf_modname(
#ifdef UNIX
                                    shortname,
#else
# ifdef SHORT_FNAME
                                    TRUE,
# else
#  ifdef FEAT_GUI_W32
                                    gui_is_win32s(),
#  else
                                    FALSE,
#  endif
# endif
#endif
                                    fname,
#ifdef VMS
                                    (char_u *)"-tmp",
#else
# ifdef RISCOS
                                    (char_u *)"/tmp",
# else
                                    (char_u *)".tmp",
# endif
#endif
                                    FALSE);
            if (tempname == NULL)               /* out of memory */
                break;

            /*
             * Check if tempfile already exists.  Never overwrite an
             * existing file!
             */
            if (mch_stat((char *)tempname, &st_new) == 0)
            {
#ifdef UNIX
                /*
                 * Check if tempfile is same as original file.  May happen
                 * when modname() gave the same file back.  E.g.  silly
                 * link, or file name-length reached.  Try again with
                 * shortname set.
                 */
                if (!shortname && st_new.st_dev == st_old.st_dev
                                            && st_new.st_ino == st_old.st_ino)
                {
                    vim_free(tempname);
                    tempname = NULL;
                    shortname = TRUE;
                    continue;
                }
#endif
                /*
                 * Try another name.  Change one character, just before
                 * the extension.  This should also work for an 8.3
                 * file name, when after adding the extension it still is
                 * the same file as the original.
                 */
                wp = tempname + STRLEN(tempname) - 5;
                if (wp < gettail(tempname))         /* empty file name? */
                    wp = gettail(tempname);
                for (*wp = 'z'; mch_stat((char *)tempname, &st_new) == 0;
                                                                    --*wp)
                {
                    /*
                     * They all exist?  Must be something wrong! Don't
                     * write the viminfo file then.
                     */
                    if (*wp == 'a')
                    {
                        vim_free(tempname);
                        tempname = NULL;
                        break;
                    }
                }
            }
            break;
        }

        if (tempname != NULL)
        {
#ifdef VMS
            /* fdopen() fails for some reason */
            umask_save = umask(077);
            fp_out = mch_fopen((char *)tempname, WRITEBIN);
            (void)umask(umask_save);
#else
            int fd;

            /* Use mch_open() to be able to use O_NOFOLLOW and set file
             * protection:
             * Unix: same as original file, but strip s-bit.  Reset umask to
             * avoid it getting in the way.
             * Others: r&w for user only. */
# ifdef UNIX
            umask_save = umask(0);
            fd = mch_open((char *)tempname,
                    O_CREAT|O_EXTRA|O_EXCL|O_WRONLY|O_NOFOLLOW,
                                       (int)((st_old.st_mode & 0777) | 0600));
            (void)umask(umask_save);
# else
            fd = mch_open((char *)tempname,
                            O_CREAT|O_EXTRA|O_EXCL|O_WRONLY|O_NOFOLLOW, 0600);
# endif
            if (fd < 0)
                fp_out = NULL;
            else
                fp_out = fdopen(fd, WRITEBIN);
#endif /* VMS */

            /*
             * If we can't create in the same directory, try creating a
             * "normal" temp file.
             */
            if (fp_out == NULL)
            {
                vim_free(tempname);
                if ((tempname = vim_tempname('o')) != NULL)
                    fp_out = mch_fopen((char *)tempname, WRITEBIN);
            }

#if defined(UNIX) && defined(HAVE_FCHOWN)
            /*
             * Make sure the owner can read/write it.  This only works for
             * root.
             */
            if (fp_out != NULL)
                (void)fchown(fileno(fp_out), st_old.st_uid, st_old.st_gid);
#endif
        }
    }

    /*
     * Check if the new viminfo file can be written to.
     */
    if (fp_out == NULL)
    {
        EMSG2(_("E138: Can't write viminfo file %s!"),
                       (fp_in == NULL || tempname == NULL) ? fname : tempname);
        if (fp_in != NULL)
            fclose(fp_in);
        goto end;
    }

    if (p_verbose > 0)
    {
        verbose_enter();
        smsg((char_u *)_("Writing viminfo file \"%s\""), fname);
        verbose_leave();
    }

    viminfo_errcnt = 0;
    do_viminfo(fp_in, fp_out, !forceit, !forceit, FALSE);

    fclose(fp_out);         /* errors are ignored !? */
    if (fp_in != NULL)
    {
        fclose(fp_in);

        /*
         * In case of an error keep the original viminfo file.
         * Otherwise rename the newly written file.
         */
        if (viminfo_errcnt || vim_rename(tempname, fname) == -1)
            mch_remove(tempname);

#ifdef WIN3264
        /* If the viminfo file was hidden then also hide the new file. */
        if (perm > 0 && (perm & FILE_ATTRIBUTE_HIDDEN))
            mch_hide(fname);
#endif
    }

end:
    vim_free(fname);
    vim_free(tempname);
}

/*
 * Get the viminfo file name to use.
 * If "file" is given and not empty, use it (has already been expanded by
 * cmdline functions).
 * Otherwise use "-i file_name", value from 'viminfo' or the default, and
 * expand environment variables.
 * Returns an allocated string.  NULL when out of memory.
 */
    static char_u *
viminfo_filename(file)
    char_u      *file;
{
    if (file == NULL || *file == NUL)
    {
        if (use_viminfo != NULL)
            file = use_viminfo;
        else if ((file = find_viminfo_parameter('n')) == NULL || *file == NUL)
        {
#ifdef VIMINFO_FILE2
            /* don't use $HOME when not defined (turned into "c:/"!). */
# ifdef VMS
            if (mch_getenv((char_u *)"SYS$LOGIN") == NULL)
# else
            if (mch_getenv((char_u *)"HOME") == NULL)
# endif
            {
                /* don't use $VIM when not available. */
                expand_env((char_u *)"$VIM", NameBuff, MAXPATHL);
                if (STRCMP("$VIM", NameBuff) != 0)  /* $VIM was expanded */
                    file = (char_u *)VIMINFO_FILE2;
                else
                    file = (char_u *)VIMINFO_FILE;
            }
            else
#endif
                file = (char_u *)VIMINFO_FILE;
        }
        expand_env(file, NameBuff, MAXPATHL);
        file = NameBuff;
    }
    return vim_strsave(file);
}

/*
 * do_viminfo() -- Should only be called from read_viminfo() & write_viminfo().
 */
    static void
do_viminfo(fp_in, fp_out, want_info, want_marks, force_read)
    FILE        *fp_in;
    FILE        *fp_out;
    int         want_info;
    int         want_marks;
    int         force_read;
{
    int         count = 0;
    int         eof = FALSE;
    vir_T       vir;

    if ((vir.vir_line = alloc(LSIZE)) == NULL)
        return;
    vir.vir_fd = fp_in;
#ifdef FEAT_MBYTE
    vir.vir_conv.vc_type = CONV_NONE;
#endif

    if (fp_in != NULL)
    {
        if (want_info)
            eof = read_viminfo_up_to_marks(&vir, force_read, fp_out != NULL);
        else
            /* Skip info, find start of marks */
            while (!(eof = viminfo_readline(&vir))
                    && vir.vir_line[0] != '>')
                ;
    }
    if (fp_out != NULL)
    {
        /* Write the info: */
        fprintf(fp_out, _("# This viminfo file was generated by Vim %s.\n"),
                                                          VIM_VERSION_MEDIUM);
        fprintf(fp_out, _("# You may edit it if you're careful!\n\n"));
#ifdef FEAT_MBYTE
        fprintf(fp_out, _("# Value of 'encoding' when this file was written\n"));
        fprintf(fp_out, "*encoding=%s\n\n", p_enc);
#endif
        write_viminfo_search_pattern(fp_out);
        write_viminfo_sub_string(fp_out);
#ifdef FEAT_CMDHIST
        write_viminfo_history(fp_out);
#endif
        write_viminfo_registers(fp_out);
#ifdef FEAT_EVAL
        write_viminfo_varlist(fp_out);
#endif
        write_viminfo_filemarks(fp_out);
        write_viminfo_bufferlist(fp_out);
        count = write_viminfo_marks(fp_out);
    }
    if (fp_in != NULL && want_marks)
        copy_viminfo_marks(&vir, fp_out, count, eof);

    vim_free(vir.vir_line);
#ifdef FEAT_MBYTE
    if (vir.vir_conv.vc_type != CONV_NONE)
        convert_setup(&vir.vir_conv, NULL, NULL);
#endif
}

/*
 * read_viminfo_up_to_marks() -- Only called from do_viminfo().  Reads in the
 * first part of the viminfo file which contains everything but the marks that
 * are local to a file.  Returns TRUE when end-of-file is reached. -- webb
 */
    static int
read_viminfo_up_to_marks(virp, forceit, writing)
    vir_T       *virp;
    int         forceit;
    int         writing;
{
    int         eof;
    buf_T       *buf;

#ifdef FEAT_CMDHIST
    prepare_viminfo_history(forceit ? 9999 : 0);
#endif
    eof = viminfo_readline(virp);
    while (!eof && virp->vir_line[0] != '>')
    {
        switch (virp->vir_line[0])
        {
                /* Characters reserved for future expansion, ignored now */
            case '+': /* "+40 /path/dir file", for running vim without args */
            case '|': /* to be defined */
            case '^': /* to be defined */
            case '<': /* long line - ignored */
                /* A comment or empty line. */
            case NUL:
            case '\r':
            case '\n':
            case '#':
                eof = viminfo_readline(virp);
                break;
            case '*': /* "*encoding=value" */
                eof = viminfo_encoding(virp);
                break;
            case '!': /* global variable */
#ifdef FEAT_EVAL
                eof = read_viminfo_varlist(virp, writing);
#else
                eof = viminfo_readline(virp);
#endif
                break;
            case '%': /* entry for buffer list */
                eof = read_viminfo_bufferlist(virp, writing);
                break;
            case '"':
                eof = read_viminfo_register(virp, forceit);
                break;
            case '/':       /* Search string */
            case '&':       /* Substitute search string */
            case '~':       /* Last search string, followed by '/' or '&' */
                eof = read_viminfo_search_pattern(virp, forceit);
                break;
            case '$':
                eof = read_viminfo_sub_string(virp, forceit);
                break;
            case ':':
            case '?':
            case '=':
            case '@':
#ifdef FEAT_CMDHIST
                eof = read_viminfo_history(virp);
#else
                eof = viminfo_readline(virp);
#endif
                break;
            case '-':
            case '\'':
                eof = read_viminfo_filemark(virp, forceit);
                break;
            default:
                if (viminfo_error("E575: ", _("Illegal starting char"),
                            virp->vir_line))
                    eof = TRUE;
                else
                    eof = viminfo_readline(virp);
                break;
        }
    }

#ifdef FEAT_CMDHIST
    /* Finish reading history items. */
    finish_viminfo_history();
#endif

    /* Change file names to buffer numbers for fmarks. */
    for (buf = firstbuf; buf != NULL; buf = buf->b_next)
        fmarks_check_names(buf);

    return eof;
}

/*
 * Compare the 'encoding' value in the viminfo file with the current value of
 * 'encoding'.  If different and the 'c' flag is in 'viminfo', setup for
 * conversion of text with iconv() in viminfo_readstring().
 */
    static int
viminfo_encoding(virp)
    vir_T       *virp;
{
#ifdef FEAT_MBYTE
    char_u      *p;
    int         i;

    if (get_viminfo_parameter('c') != 0)
    {
        p = vim_strchr(virp->vir_line, '=');
        if (p != NULL)
        {
            /* remove trailing newline */
            ++p;
            for (i = 0; vim_isprintc(p[i]); ++i)
                ;
            p[i] = NUL;

            convert_setup(&virp->vir_conv, p, p_enc);
        }
    }
#endif
    return viminfo_readline(virp);
}

/*
 * Read a line from the viminfo file.
 * Returns TRUE for end-of-file;
 */
    int
viminfo_readline(virp)
    vir_T       *virp;
{
    return vim_fgets(virp->vir_line, LSIZE, virp->vir_fd);
}

/*
 * check string read from viminfo file
 * remove '\n' at the end of the line
 * - replace CTRL-V CTRL-V with CTRL-V
 * - replace CTRL-V 'n'    with '\n'
 *
 * Check for a long line as written by viminfo_writestring().
 *
 * Return the string in allocated memory (NULL when out of memory).
 */
/*ARGSUSED*/
    char_u *
viminfo_readstring(virp, off, convert)
    vir_T       *virp;
    int         off;                /* offset for virp->vir_line */
    int         convert;            /* convert the string */
{
    char_u      *retval;
    char_u      *s, *d;
    long        len;

    if (virp->vir_line[off] == Ctrl_V && vim_isdigit(virp->vir_line[off + 1]))
    {
        len = atol((char *)virp->vir_line + off + 1);
        retval = lalloc(len, TRUE);
        if (retval == NULL)
        {
            /* Line too long?  File messed up?  Skip next line. */
            (void)vim_fgets(virp->vir_line, 10, virp->vir_fd);
            return NULL;
        }
        (void)vim_fgets(retval, (int)len, virp->vir_fd);
        s = retval + 1;     /* Skip the leading '<' */
    }
    else
    {
        retval = vim_strsave(virp->vir_line + off);
        if (retval == NULL)
            return NULL;
        s = retval;
    }

    /* Change CTRL-V CTRL-V to CTRL-V and CTRL-V n to \n in-place. */
    d = retval;
    while (*s != NUL && *s != '\n')
    {
        if (s[0] == Ctrl_V && s[1] != NUL)
        {
            if (s[1] == 'n')
                *d++ = '\n';
            else
                *d++ = Ctrl_V;
            s += 2;
        }
        else
            *d++ = *s++;
    }
    *d = NUL;

#ifdef FEAT_MBYTE
    if (convert && virp->vir_conv.vc_type != CONV_NONE && *retval != NUL)
    {
        d = string_convert(&virp->vir_conv, retval, NULL);
        if (d != NULL)
        {
            vim_free(retval);
            retval = d;
        }
    }
#endif

    return retval;
}

/*
 * write string to viminfo file
 * - replace CTRL-V with CTRL-V CTRL-V
 * - replace '\n'   with CTRL-V 'n'
 * - add a '\n' at the end
 *
 * For a long line:
 * - write " CTRL-V <length> \n " in first line
 * - write " < <string> \n "      in second line
 */
    void
viminfo_writestring(fd, p)
    FILE        *fd;
    char_u      *p;
{
    int         c;
    char_u      *s;
    int         len = 0;

    for (s = p; *s != NUL; ++s)
    {
        if (*s == Ctrl_V || *s == '\n')
            ++len;
        ++len;
    }

    /* If the string will be too long, write its length and put it in the next
     * line.  Take into account that some room is needed for what comes before
     * the string (e.g., variable name).  Add something to the length for the
     * '<', NL and trailing NUL. */
    if (len > LSIZE / 2)
        fprintf(fd, IF_EB("\026%d\n<", CTRL_V_STR "%d\n<"), len + 3);

    while ((c = *p++) != NUL)
    {
        if (c == Ctrl_V || c == '\n')
        {
            putc(Ctrl_V, fd);
            if (c == '\n')
                c = 'n';
        }
        putc(c, fd);
    }
    putc('\n', fd);
}
#endif /* FEAT_VIMINFO */

/*
 * Implementation of ":fixdel", also used by get_stty().
 *  <BS>    resulting <Del>
 *   ^?         ^H
 * not ^?       ^?
 */
/*ARGSUSED*/
    void
do_fixdel(eap)
    exarg_T     *eap;
{
    char_u  *p;

    p = find_termcode((char_u *)"kb");
    add_termcode((char_u *)"kD", p != NULL
            && *p == DEL ? (char_u *)CTRL_H_STR : DEL_STR, FALSE);
}

    void
print_line_no_prefix(lnum, use_number, list)
    linenr_T    lnum;
    int         use_number;
    int         list;
{
    char_u      numbuf[30];

    if (curwin->w_p_nu || use_number)
    {
        sprintf((char *)numbuf, "%*ld ", number_width(curwin), (long)lnum);
        msg_puts_attr(numbuf, hl_attr(HLF_N));  /* Highlight line nrs */
    }
    msg_prt_line(ml_get(lnum), list);
}

/*
 * Print a text line.  Also in silent mode ("ex -s").
 */
    void
print_line(lnum, use_number, list)
    linenr_T    lnum;
    int         use_number;
    int         list;
{
    int         save_silent = silent_mode;

    msg_start();
    silent_mode = FALSE;
    info_message = TRUE;        /* use mch_msg(), not mch_errmsg() */
    print_line_no_prefix(lnum, use_number, list);
    if (save_silent)
    {
        msg_putchar('\n');
        cursor_on();            /* msg_start() switches it off */
        out_flush();
        silent_mode = save_silent;
        info_message = FALSE;
    }
}

/*
 * ":file[!] [fname]".
 */
    void
ex_file(eap)
    exarg_T     *eap;
{
    char_u      *fname, *sfname, *xfname;
    buf_T       *buf;

    /* ":0file" removes the file name.  Check for illegal uses ":3file",
     * "0file name", etc. */
    if (eap->addr_count > 0
            && (*eap->arg != NUL
                || eap->line2 > 0
                || eap->addr_count > 1))
    {
        EMSG(_(e_invarg));
        return;
    }

    if (*eap->arg != NUL || eap->addr_count == 1)
    {
#ifdef FEAT_AUTOCMD
        buf = curbuf;
        apply_autocmds(EVENT_BUFFILEPRE, NULL, NULL, FALSE, curbuf);
        /* buffer changed, don't change name now */
        if (buf != curbuf)
            return;
# ifdef FEAT_EVAL
        if (aborting())     /* autocmds may abort script processing */
            return;
# endif
#endif
        /*
         * The name of the current buffer will be changed.
         * A new (unlisted) buffer entry needs to be made to hold the old file
         * name, which will become the alternate file name.
         * But don't set the alternate file name if the buffer didn't have a
         * name.
         */
        fname = curbuf->b_ffname;
        sfname = curbuf->b_sfname;
        xfname = curbuf->b_fname;
        curbuf->b_ffname = NULL;
        curbuf->b_sfname = NULL;
        if (setfname(curbuf, eap->arg, NULL, TRUE) == FAIL)
        {
            curbuf->b_ffname = fname;
            curbuf->b_sfname = sfname;
            return;
        }
        curbuf->b_flags |= BF_NOTEDITED;
        if (xfname != NULL && *xfname != NUL)
        {
            buf = buflist_new(fname, xfname, curwin->w_cursor.lnum, 0);
            if (buf != NULL && !cmdmod.keepalt)
                curwin->w_alt_fnum = buf->b_fnum;
        }
        vim_free(fname);
        vim_free(sfname);
#ifdef FEAT_AUTOCMD
        apply_autocmds(EVENT_BUFFILEPOST, NULL, NULL, FALSE, curbuf);
#endif
        /* Change directories when the 'acd' option is set. */
        DO_AUTOCHDIR
    }
    /* print full file name if :cd used */
    fileinfo(FALSE, FALSE, eap->forceit);
}

/*
 * ":update".
 */
    void
ex_update(eap)
    exarg_T     *eap;
{
    if (curbufIsChanged())
        (void)do_write(eap);
}

/*
 * ":write" and ":saveas".
 */
    void
ex_write(eap)
    exarg_T     *eap;
{
    if (eap->usefilter)         /* input lines to shell command */
        do_bang(1, eap, FALSE, TRUE, FALSE);
    else
        (void)do_write(eap);
}

/*
 * write current buffer to file 'eap->arg'
 * if 'eap->append' is TRUE, append to the file
 *
 * if *eap->arg == NUL write to current file
 *
 * return FAIL for failure, OK otherwise
 */
    int
do_write(eap)
    exarg_T     *eap;
{
    int         other;
    char_u      *fname = NULL;          /* init to shut up gcc */
    char_u      *ffname;
    int         retval = FAIL;
    char_u      *free_fname = NULL;
#ifdef FEAT_BROWSE
    char_u      *browse_file = NULL;
#endif
    buf_T       *alt_buf = NULL;

    if (not_writing())          /* check 'write' option */
        return FAIL;

    ffname = eap->arg;
#ifdef FEAT_BROWSE
    if (cmdmod.browse)
    {
        browse_file = do_browse(BROWSE_SAVE, (char_u *)_("Save As"), ffname,
                                                    NULL, NULL, NULL, curbuf);
        if (browse_file == NULL)
            goto theend;
        ffname = browse_file;
    }
#endif
    if (*ffname == NUL)
    {
        if (eap->cmdidx == CMD_saveas)
        {
            EMSG(_(e_argreq));
            goto theend;
        }
        other = FALSE;
    }
    else
    {
        fname = ffname;
        free_fname = fix_fname(ffname);
        /*
         * When out-of-memory, keep unexpanded file name, because we MUST be
         * able to write the file in this situation.
         */
        if (free_fname != NULL)
            ffname = free_fname;
        other = otherfile(ffname);
    }

    /*
     * If we have a new file, put its name in the list of alternate file names.
     */
    if (other)
    {
        if (vim_strchr(p_cpo, CPO_ALTWRITE) != NULL
                                                 || eap->cmdidx == CMD_saveas)
            alt_buf = setaltfname(ffname, fname, (linenr_T)1);
        else
            alt_buf = buflist_findname(ffname);
        if (alt_buf != NULL && alt_buf->b_ml.ml_mfp != NULL)
        {
            /* Overwriting a file that is loaded in another buffer is not a
             * good idea. */
            EMSG(_(e_bufloaded));
            goto theend;
        }
    }

    /*
     * Writing to the current file is not allowed in readonly mode
     * and a file name is required.
     * "nofile" and "nowrite" buffers cannot be written implicitly either.
     */
    if (!other && (
#ifdef FEAT_QUICKFIX
                bt_dontwrite_msg(curbuf) ||
#endif
                check_fname() == FAIL || check_readonly(&eap->forceit, curbuf)))
        goto theend;

    if (!other)
    {
        ffname = curbuf->b_ffname;
        fname = curbuf->b_fname;
        /*
         * Not writing the whole file is only allowed with '!'.
         */
        if (       (eap->line1 != 1
                    || eap->line2 != curbuf->b_ml.ml_line_count)
                && !eap->forceit
                && !eap->append
                && !p_wa)
        {
#if defined(FEAT_GUI_DIALOG) || defined(FEAT_CON_DIALOG)
            if (p_confirm || cmdmod.confirm)
            {
                if (vim_dialog_yesno(VIM_QUESTION, NULL,
                               (char_u *)_("Write partial file?"), 2) != VIM_YES)
                    goto theend;
                eap->forceit = TRUE;
            }
            else
#endif
            {
                EMSG(_("E140: Use ! to write partial buffer"));
                goto theend;
            }
        }
    }

    if (check_overwrite(eap, curbuf, fname, ffname, other) == OK)
    {
        if (eap->cmdidx == CMD_saveas && alt_buf != NULL)
        {
#ifdef FEAT_AUTOCMD
            buf_T       *was_curbuf = curbuf;

            apply_autocmds(EVENT_BUFFILEPRE, NULL, NULL, FALSE, curbuf);
            apply_autocmds(EVENT_BUFFILEPRE, NULL, NULL, FALSE, alt_buf);
# ifdef FEAT_EVAL
            if (curbuf != was_curbuf || aborting())
# else
            if (curbuf != was_curbuf)
# endif
            {
                /* buffer changed, don't change name now */
                retval = FAIL;
                goto theend;
            }
#endif
            /* Exchange the file names for the current and the alternate
             * buffer.  This makes it look like we are now editing the buffer
             * under the new name.  Must be done before buf_write(), because
             * if there is no file name and 'cpo' contains 'F', it will set
             * the file name. */
            fname = alt_buf->b_fname;
            alt_buf->b_fname = curbuf->b_fname;
            curbuf->b_fname = fname;
            fname = alt_buf->b_ffname;
            alt_buf->b_ffname = curbuf->b_ffname;
            curbuf->b_ffname = fname;
            fname = alt_buf->b_sfname;
            alt_buf->b_sfname = curbuf->b_sfname;
            curbuf->b_sfname = fname;
            buf_name_changed(curbuf);
#ifdef FEAT_AUTOCMD
            apply_autocmds(EVENT_BUFFILEPOST, NULL, NULL, FALSE, curbuf);
            apply_autocmds(EVENT_BUFFILEPOST, NULL, NULL, FALSE, alt_buf);
            if (!alt_buf->b_p_bl)
            {
                alt_buf->b_p_bl = TRUE;
                apply_autocmds(EVENT_BUFADD, NULL, NULL, FALSE, alt_buf);
            }
# ifdef FEAT_EVAL
            if (curbuf != was_curbuf || aborting())
# else
            if (curbuf != was_curbuf)
# endif
            {
                /* buffer changed, don't write the file */
                retval = FAIL;
                goto theend;
            }

            /* If 'filetype' was empty try detecting it now. */
            if (*curbuf->b_p_ft == NUL)
            {
                if (au_has_group((char_u *)"filetypedetect"))
                    (void)do_doautocmd((char_u *)"filetypedetect BufRead",
                                                                        TRUE);
                do_modelines(0);
            }
#endif
        }

        retval = buf_write(curbuf, ffname, fname, eap->line1, eap->line2,
                                 eap, eap->append, eap->forceit, TRUE, FALSE);

        /* After ":saveas fname" reset 'readonly'. */
        if (eap->cmdidx == CMD_saveas)
        {
            if (retval == OK)
                curbuf->b_p_ro = FALSE;
            /* Change directories when the 'acd' option is set. */
            DO_AUTOCHDIR
        }
    }

theend:
#ifdef FEAT_BROWSE
    vim_free(browse_file);
#endif
    vim_free(free_fname);
    return retval;
}

/*
 * Check if it is allowed to overwrite a file.  If b_flags has BF_NOTEDITED,
 * BF_NEW or BF_READERR, check for overwriting current file.
 * May set eap->forceit if a dialog says it's OK to overwrite.
 * Return OK if it's OK, FAIL if it is not.
 */
/*ARGSUSED*/
    static int
check_overwrite(eap, buf, fname, ffname, other)
    exarg_T     *eap;
    buf_T       *buf;
    char_u      *fname;     /* file name to be used (can differ from
                               buf->ffname) */
    char_u      *ffname;    /* full path version of fname */
    int         other;      /* writing under other name */
{
    /*
     * write to other file or b_flags set or not writing the whole file:
     * overwriting only allowed with '!'
     */
    if (       (other
                || (buf->b_flags & BF_NOTEDITED)
                || ((buf->b_flags & BF_NEW)
                    && vim_strchr(p_cpo, CPO_OVERNEW) == NULL)
                || (buf->b_flags & BF_READERR))
            && !p_wa
#ifdef FEAT_QUICKFIX
            && !bt_nofile(buf)
#endif
            && vim_fexists(ffname))
    {
        if (!eap->forceit && !eap->append)
        {
#ifdef UNIX
            /* with UNIX it is possible to open a directory */
            if (mch_isdir(ffname))
            {
                EMSG2(_(e_isadir2), ffname);
                return FAIL;
            }
#endif
#if defined(FEAT_GUI_DIALOG) || defined(FEAT_CON_DIALOG)
            if (p_confirm || cmdmod.confirm)
            {
                char_u  buff[IOSIZE];

                dialog_msg(buff, _("Overwrite existing file \"%s\"?"), fname);
                if (vim_dialog_yesno(VIM_QUESTION, NULL, buff, 2) != VIM_YES)
                    return FAIL;
                eap->forceit = TRUE;
            }
            else
#endif
            {
                EMSG(_(e_exists));
                return FAIL;
            }
        }

        /* For ":w! filename" check that no swap file exists for "filename". */
        if (other && !emsg_silent)
        {
            char_u      dir[MAXPATHL];
            char_u      *p;
            int         r;
            char_u      *swapname;

            /* We only try the first entry in 'directory', without checking if
             * it's writable.  If the "." directory is not writable the write
             * will probably fail anyway.
             * Use 'shortname' of the current buffer, since there is no buffer
             * for the written file. */
            if (*p_dir == NUL)
                STRCPY(dir, ".");
            else
            {
                p = p_dir;
                copy_option_part(&p, dir, MAXPATHL, ",");
            }
            swapname = makeswapname(fname, ffname, curbuf, dir);
            r = vim_fexists(swapname);
            if (r)
            {
#if defined(FEAT_GUI_DIALOG) || defined(FEAT_CON_DIALOG)
                if (p_confirm || cmdmod.confirm)
                {
                    char_u      buff[IOSIZE];

                    dialog_msg(buff,
                            _("Swap file \"%s\" exists, overwrite anyway?"),
                                                                    swapname);
                    if (vim_dialog_yesno(VIM_QUESTION, NULL, buff, 2)
                                                                   != VIM_YES)
                    {
                        vim_free(swapname);
                        return FAIL;
                    }
                    eap->forceit = TRUE;
                }
                else
#endif
                {
                    EMSG2(_("E768: Swap file exists: %s (:silent! overrides)"),
                                                                    swapname);
                    vim_free(swapname);
                    return FAIL;
                }
            }
            vim_free(swapname);
        }
    }
    return OK;
}

/*
 * Handle ":wnext", ":wNext" and ":wprevious" commands.
 */
    void
ex_wnext(eap)
    exarg_T     *eap;
{
    int         i;

    if (eap->cmd[1] == 'n')
        i = curwin->w_arg_idx + (int)eap->line2;
    else
        i = curwin->w_arg_idx - (int)eap->line2;
    eap->line1 = 1;
    eap->line2 = curbuf->b_ml.ml_line_count;
    if (do_write(eap) != FAIL)
        do_argfile(eap, i);
}

/*
 * ":wall", ":wqall" and ":xall": Write all changed files (and exit).
 */
    void
do_wqall(eap)
    exarg_T     *eap;
{
    buf_T       *buf;
    int         error = 0;
    int         save_forceit = eap->forceit;

    if (eap->cmdidx == CMD_xall || eap->cmdidx == CMD_wqall)
        exiting = TRUE;

    for (buf = firstbuf; buf != NULL; buf = buf->b_next)
    {
        if (bufIsChanged(buf))
        {
            /*
             * Check if there is a reason the buffer cannot be written:
             * 1. if the 'write' option is set
             * 2. if there is no file name (even after browsing)
             * 3. if the 'readonly' is set (even after a dialog)
             * 4. if overwriting is allowed (even after a dialog)
             */
            if (not_writing())
            {
                ++error;
                break;
            }
#ifdef FEAT_BROWSE
            /* ":browse wall": ask for file name if there isn't one */
            if (buf->b_ffname == NULL && cmdmod.browse)
                browse_save_fname(buf);
#endif
            if (buf->b_ffname == NULL)
            {
                EMSGN(_("E141: No file name for buffer %ld"), (long)buf->b_fnum);
                ++error;
            }
            else if (check_readonly(&eap->forceit, buf)
                    || check_overwrite(eap, buf, buf->b_fname, buf->b_ffname,
                                                               FALSE) == FAIL)
            {
                ++error;
            }
            else
            {
                if (buf_write_all(buf, eap->forceit) == FAIL)
                    ++error;
#ifdef FEAT_AUTOCMD
                /* an autocommand may have deleted the buffer */
                if (!buf_valid(buf))
                    buf = firstbuf;
#endif
            }
            eap->forceit = save_forceit;    /* check_overwrite() may set it */
        }
    }
    if (exiting)
    {
        if (!error)
            getout(0);          /* exit Vim */
        not_exiting();
    }
}

/*
 * Check the 'write' option.
 * Return TRUE and give a message when it's not st.
 */
    int
not_writing()
{
    if (p_write)
        return FALSE;
    EMSG(_("E142: File not written: Writing is disabled by 'write' option"));
    return TRUE;
}

/*
 * Check if a buffer is read-only (either 'readonly' option is set or file is
 * read-only). Ask for overruling in a dialog. Return TRUE and give an error
 * message when the buffer is readonly.
 */
    static int
check_readonly(forceit, buf)
    int         *forceit;
    buf_T       *buf;
{
    struct stat st;

    /* Handle a file being readonly when the 'readonly' option is set or when
     * the file exists and permissions are read-only.
     * We will send 0777 to check_file_readonly(), as the "perm" variable is
     * important for device checks but not here. */
    if (!*forceit && (buf->b_p_ro
                || (mch_stat((char *)buf->b_ffname, &st) >= 0
                    && check_file_readonly(buf->b_ffname, 0777))))
    {
#if defined(FEAT_GUI_DIALOG) || defined(FEAT_CON_DIALOG)
        if ((p_confirm || cmdmod.confirm) && buf->b_fname != NULL)
        {
            char_u      buff[IOSIZE];

            if (buf->b_p_ro)
                dialog_msg(buff, _("'readonly' option is set for \"%s\".\nDo you wish to write anyway?"),
                    buf->b_fname);
            else
                dialog_msg(buff, _("File permissions of \"%s\" are read-only.\nIt may still be possible to write it.\nDo you wish to try?"),
                    buf->b_fname);

            if (vim_dialog_yesno(VIM_QUESTION, NULL, buff, 2) == VIM_YES)
            {
                /* Set forceit, to force the writing of a readonly file */
                *forceit = TRUE;
                return FALSE;
            }
            else
                return TRUE;
        }
        else
#endif
        if (buf->b_p_ro)
            EMSG(_(e_readonly));
        else
            EMSG2(_("E505: \"%s\" is read-only (add ! to override)"),
                    buf->b_fname);
        return TRUE;
    }

    return FALSE;
}

/*
 * Try to abandon current file and edit a new or existing file.
 * 'fnum' is the number of the file, if zero use ffname/sfname.
 *
 * Return 1 for "normal" error, 2 for "not written" error, 0 for success
 * -1 for successfully opening another file.
 * 'lnum' is the line number for the cursor in the new file (if non-zero).
 */
    int
getfile(fnum, ffname, sfname, setpm, lnum, forceit)
    int         fnum;
    char_u      *ffname;
    char_u      *sfname;
    int         setpm;
    linenr_T    lnum;
    int         forceit;
{
    int         other;
    int         retval;
    char_u      *free_me = NULL;

    if (text_locked())
        return 1;
#ifdef FEAT_AUTOCMD
    if (curbuf_locked())
        return 1;
#endif

    if (fnum == 0)
    {
                                        /* make ffname full path, set sfname */
        fname_expand(curbuf, &ffname, &sfname);
        other = otherfile(ffname);
        free_me = ffname;               /* has been allocated, free() later */
    }
    else
        other = (fnum != curbuf->b_fnum);

    if (other)
        ++no_wait_return;           /* don't wait for autowrite message */
    if (other && !forceit && curbuf->b_nwindows == 1 && !P_HID(curbuf)
                   && curbufIsChanged() && autowrite(curbuf, forceit) == FAIL)
    {
#if defined(FEAT_GUI_DIALOG) || defined(FEAT_CON_DIALOG)
        if (p_confirm && p_write)
            dialog_changed(curbuf, FALSE);
        if (curbufIsChanged())
#endif
        {
            if (other)
                --no_wait_return;
            EMSG(_(e_nowrtmsg));
            retval = 2; /* file has been changed */
            goto theend;
        }
    }
    if (other)
        --no_wait_return;
    if (setpm)
        setpcmark();
    if (!other)
    {
        if (lnum != 0)
            curwin->w_cursor.lnum = lnum;
        check_cursor_lnum();
        beginline(BL_SOL | BL_FIX);
        retval = 0;     /* it's in the same file */
    }
    else if (do_ecmd(fnum, ffname, sfname, NULL, lnum,
                (P_HID(curbuf) ? ECMD_HIDE : 0) + (forceit ? ECMD_FORCEIT : 0)) == OK)
        retval = -1;    /* opened another file */
    else
        retval = 1;     /* error encountered */

theend:
    vim_free(free_me);
    return retval;
}

/*
 * start editing a new file
 *
 *     fnum: file number; if zero use ffname/sfname
 *   ffname: the file name
 *              - full path if sfname used,
 *              - any file name if sfname is NULL
 *              - empty string to re-edit with the same file name (but may be
 *                  in a different directory)
 *              - NULL to start an empty buffer
 *   sfname: the short file name (or NULL)
 *      eap: contains the command to be executed after loading the file and
 *           forced 'ff' and 'fenc'
 *  newlnum: if > 0: put cursor on this line number (if possible)
 *           if ECMD_LASTL: use last position in loaded file
 *           if ECMD_LAST: use last position in all files
 *           if ECMD_ONE: use first line
 *    flags:
 *         ECMD_HIDE: if TRUE don't free the current buffer
 *     ECMD_SET_HELP: set b_help flag of (new) buffer before opening file
 *       ECMD_OLDBUF: use existing buffer if it exists
 *      ECMD_FORCEIT: ! used for Ex command
 *       ECMD_ADDBUF: don't edit, just add to buffer list
 *
 * return FAIL for failure, OK otherwise
 */
    int
do_ecmd(fnum, ffname, sfname, eap, newlnum, flags)
    int         fnum;
    char_u      *ffname;
    char_u      *sfname;
    exarg_T     *eap;                   /* can be NULL! */
    linenr_T    newlnum;
    int         flags;
{
    int         other_file;             /* TRUE if editing another file */
    int         oldbuf;                 /* TRUE if using existing buffer */
#ifdef FEAT_AUTOCMD
    int         auto_buf = FALSE;       /* TRUE if autocommands brought us
                                           into the buffer unexpectedly */
    char_u      *new_name = NULL;
    int         did_set_swapcommand = FALSE;
#endif
    buf_T       *buf;
#if defined(FEAT_AUTOCMD) || defined(FEAT_GUI_DIALOG) || defined(FEAT_CON_DIALOG)
    buf_T       *old_curbuf = curbuf;
#endif
    char_u      *free_fname = NULL;
#ifdef FEAT_BROWSE
    char_u      *browse_file = NULL;
#endif
    int         retval = FAIL;
    long        n;
    linenr_T    lnum;
    linenr_T    topline = 0;
    int         newcol = -1;
    int         solcol = -1;
    pos_T       *pos;
#ifdef FEAT_SUN_WORKSHOP
    char_u      *cp;
#endif
    char_u      *command = NULL;
#ifdef FEAT_SPELL
    int         did_get_winopts = FALSE;
#endif

    if (eap != NULL)
        command = eap->do_ecmd_cmd;

    if (fnum != 0)
    {
        if (fnum == curbuf->b_fnum)     /* file is already being edited */
            return OK;                  /* nothing to do */
        other_file = TRUE;
    }
    else
    {
#ifdef FEAT_BROWSE
        if (cmdmod.browse)
        {
# ifdef FEAT_AUTOCMD
            if (
#  ifdef FEAT_GUI
                !gui.in_use &&
#  endif
                    au_has_group((char_u *)"FileExplorer"))
            {
                /* No browsing supported but we do have the file explorer:
                 * Edit the directory. */
                if (ffname == NULL || !mch_isdir(ffname))
                    ffname = (char_u *)".";
            }
            else
# endif
            {
                browse_file = do_browse(0, (char_u *)_("Edit File"), ffname,
                                                    NULL, NULL, NULL, curbuf);
                if (browse_file == NULL)
                    goto theend;
                ffname = browse_file;
            }
        }
#endif
        /* if no short name given, use ffname for short name */
        if (sfname == NULL)
            sfname = ffname;
#ifdef USE_FNAME_CASE
# ifdef USE_LONG_FNAME
        if (USE_LONG_FNAME)
# endif
            if (sfname != NULL)
                fname_case(sfname, 0);   /* set correct case for sfname */
#endif

#ifdef FEAT_LISTCMDS
        if ((flags & ECMD_ADDBUF) && (ffname == NULL || *ffname == NUL))
            goto theend;
#endif

        if (ffname == NULL)
            other_file = TRUE;
                                            /* there is no file name */
        else if (*ffname == NUL && curbuf->b_ffname == NULL)
            other_file = FALSE;
        else
        {
            if (*ffname == NUL)             /* re-edit with same file name */
            {
                ffname = curbuf->b_ffname;
                sfname = curbuf->b_fname;
            }
            free_fname = fix_fname(ffname); /* may expand to full path name */
            if (free_fname != NULL)
                ffname = free_fname;
            other_file = otherfile(ffname);
#ifdef FEAT_SUN_WORKSHOP
            if (usingSunWorkShop && p_acd
                                   && (cp = vim_strrchr(sfname, '/')) != NULL)
                sfname = ++cp;
#endif
        }
    }

    /*
     * if the file was changed we may not be allowed to abandon it
     * - if we are going to re-edit the same file
     * - or if we are the only window on this file and if ECMD_HIDE is FALSE
     */
    if (  ((!other_file && !(flags & ECMD_OLDBUF))
            || (curbuf->b_nwindows == 1
                && !(flags & (ECMD_HIDE | ECMD_ADDBUF))))
        && check_changed(curbuf, p_awa, !other_file,
                                        (flags & ECMD_FORCEIT), FALSE))
    {
        if (fnum == 0 && other_file && ffname != NULL)
            (void)setaltfname(ffname, sfname, newlnum < 0 ? 0 : newlnum);
        goto theend;
    }

#ifdef FEAT_VISUAL
    /*
     * End Visual mode before switching to another buffer, so the text can be
     * copied into the GUI selection buffer.
     */
    reset_VIsual();
#endif

#ifdef FEAT_AUTOCMD
    if ((command != NULL || newlnum > (linenr_T)0)
            && *get_vim_var_str(VV_SWAPCOMMAND) == NUL)
    {
        int     len;
        char_u  *p;

        /* Set v:swapcommand for the SwapExists autocommands. */
        if (command != NULL)
            len = (int)STRLEN(command) + 3;
        else
            len = 30;
        p = alloc((unsigned)len);
        if (p != NULL)
        {
            if (command != NULL)
                vim_snprintf((char *)p, len, ":%s\r", command);
            else
                vim_snprintf((char *)p, len, "%ldG", (long)newlnum);
            set_vim_var_string(VV_SWAPCOMMAND, p, -1);
            did_set_swapcommand = TRUE;
            vim_free(p);
        }
    }
#endif

    /*
     * If we are starting to edit another file, open a (new) buffer.
     * Otherwise we re-use the current buffer.
     */
    if (other_file)
    {
#ifdef FEAT_LISTCMDS
        if (!(flags & ECMD_ADDBUF))
#endif
        {
            if (!cmdmod.keepalt)
                curwin->w_alt_fnum = curbuf->b_fnum;
            buflist_altfpos();
        }

        if (fnum)
            buf = buflist_findnr(fnum);
        else
        {
#ifdef FEAT_LISTCMDS
            if (flags & ECMD_ADDBUF)
            {
                linenr_T        tlnum = 1L;

                if (command != NULL)
                {
                    tlnum = atol((char *)command);
                    if (tlnum <= 0)
                        tlnum = 1L;
                }
                (void)buflist_new(ffname, sfname, tlnum, BLN_LISTED);
                goto theend;
            }
#endif
            buf = buflist_new(ffname, sfname, 0L,
                    BLN_CURBUF | ((flags & ECMD_SET_HELP) ? 0 : BLN_LISTED));
        }
        if (buf == NULL)
            goto theend;
        if (buf->b_ml.ml_mfp == NULL)           /* no memfile yet */
        {
            oldbuf = FALSE;
            buf->b_nwindows = 0;
        }
        else                                    /* existing memfile */
        {
            oldbuf = TRUE;
            (void)buf_check_timestamp(buf, FALSE);
            /* Check if autocommands made buffer invalid or changed the current
             * buffer. */
            if (!buf_valid(buf)
#ifdef FEAT_AUTOCMD
                    || curbuf != old_curbuf
#endif
                    )
                goto theend;
#ifdef FEAT_EVAL
            if (aborting())         /* autocmds may abort script processing */
                goto theend;
#endif
        }

        /* May jump to last used line number for a loaded buffer or when asked
         * for explicitly */
        if ((oldbuf && newlnum == ECMD_LASTL) || newlnum == ECMD_LAST)
        {
            pos = buflist_findfpos(buf);
            newlnum = pos->lnum;
            solcol = pos->col;
        }

        /*
         * Make the (new) buffer the one used by the current window.
         * If the old buffer becomes unused, free it if ECMD_HIDE is FALSE.
         * If the current buffer was empty and has no file name, curbuf
         * is returned by buflist_new().
         */
        if (buf != curbuf)
        {
#ifdef FEAT_AUTOCMD
            /*
             * Be careful: The autocommands may delete any buffer and change
             * the current buffer.
             * - If the buffer we are going to edit is deleted, give up.
             * - If the current buffer is deleted, prefer to load the new
             *   buffer when loading a buffer is required.  This avoids
             *   loading another buffer which then must be closed again.
             * - If we ended up in the new buffer already, need to skip a few
             *   things, set auto_buf.
             */
            if (buf->b_fname != NULL)
                new_name = vim_strsave(buf->b_fname);
            au_new_curbuf = buf;
            apply_autocmds(EVENT_BUFLEAVE, NULL, NULL, FALSE, curbuf);
            if (!buf_valid(buf))        /* new buffer has been deleted */
            {
                delbuf_msg(new_name);   /* frees new_name */
                goto theend;
            }
# ifdef FEAT_EVAL
            if (aborting())         /* autocmds may abort script processing */
            {
                vim_free(new_name);
                goto theend;
            }
# endif
            if (buf == curbuf)          /* already in new buffer */
                auto_buf = TRUE;
            else
            {
                if (curbuf == old_curbuf)
#endif
                    buf_copy_options(buf, BCO_ENTER);

                /* close the link to the current buffer */
                u_sync(FALSE);
                close_buffer(curwin, curbuf,
                                      (flags & ECMD_HIDE) ? 0 : DOBUF_UNLOAD);

#ifdef FEAT_AUTOCMD
# ifdef FEAT_EVAL
                if (aborting())     /* autocmds may abort script processing */
                {
                    vim_free(new_name);
                    goto theend;
                }
# endif
                /* Be careful again, like above. */
                if (!buf_valid(buf))    /* new buffer has been deleted */
                {
                    delbuf_msg(new_name);       /* frees new_name */
                    goto theend;
                }
                if (buf == curbuf)              /* already in new buffer */
                    auto_buf = TRUE;
                else
#endif
                {
                    curwin->w_buffer = buf;
                    curbuf = buf;
                    ++curbuf->b_nwindows;
                    /* set 'fileformat' */
                    if (*p_ffs && !oldbuf)
                        set_fileformat(default_fileformat(), OPT_LOCAL);
                }

                /* May get the window options from the last time this buffer
                 * was in this window (or another window).  If not used
                 * before, reset the local window options to the global
                 * values.  Also restores old folding stuff. */
                get_winopts(curbuf);
#ifdef FEAT_SPELL
                did_get_winopts = TRUE;
#endif

#ifdef FEAT_AUTOCMD
            }
            vim_free(new_name);
            au_new_curbuf = NULL;
#endif
        }
        else
            ++curbuf->b_nwindows;

        curwin->w_pcmark.lnum = 1;
        curwin->w_pcmark.col = 0;
    }
    else /* !other_file */
    {
        if (
#ifdef FEAT_LISTCMDS
                (flags & ECMD_ADDBUF) ||
#endif
                check_fname() == FAIL)
            goto theend;
        oldbuf = (flags & ECMD_OLDBUF);
    }

    if ((flags & ECMD_SET_HELP) || keep_help_flag)
    {
        char_u  *p;

        curbuf->b_help = TRUE;
#ifdef FEAT_QUICKFIX
        set_string_option_direct((char_u *)"buftype", -1,
                                     (char_u *)"help", OPT_FREE|OPT_LOCAL, 0);
#endif

        /*
         * Always set these options after jumping to a help tag, because the
         * user may have an autocommand that gets in the way.
         * Accept all ASCII chars for keywords, except ' ', '*', '"', '|', and
         * latin1 word characters (for translated help files).
         * Only set it when needed, buf_init_chartab() is some work.
         */
        p =
#ifdef EBCDIC
                (char_u *)"65-255,^*,^|,^\"";
#else
                (char_u *)"!-~,^*,^|,^\",192-255";
#endif
        if (STRCMP(curbuf->b_p_isk, p) != 0)
        {
            set_string_option_direct((char_u *)"isk", -1, p,
                                                       OPT_FREE|OPT_LOCAL, 0);
            check_buf_options(curbuf);
            (void)buf_init_chartab(curbuf, FALSE);
        }

        curbuf->b_p_ts = 8;             /* 'tabstop' is 8 */
        curwin->w_p_list = FALSE;       /* no list mode */

        curbuf->b_p_ma = FALSE;         /* not modifiable */
        curbuf->b_p_bin = FALSE;        /* reset 'bin' before reading file */
        curwin->w_p_nu = 0;             /* no line numbers */
#ifdef FEAT_SCROLLBIND
        curwin->w_p_scb = FALSE;        /* no scroll binding */
#endif
#ifdef FEAT_ARABIC
        curwin->w_p_arab = FALSE;       /* no arabic mode */
#endif
#ifdef FEAT_RIGHTLEFT
        curwin->w_p_rl  = FALSE;        /* help window is left-to-right */
#endif
#ifdef FEAT_FOLDING
        curwin->w_p_fen = FALSE;        /* No folding in the help window */
#endif
#ifdef FEAT_DIFF
        curwin->w_p_diff = FALSE;       /* No 'diff' */
#endif
#ifdef FEAT_SPELL
        curwin->w_p_spell = FALSE;      /* No spell checking */
#endif

#ifdef FEAT_AUTOCMD
        buf = curbuf;
#endif
        set_buflisted(FALSE);
    }
    else
    {
#ifdef FEAT_AUTOCMD
        buf = curbuf;
#endif
        /* Don't make a buffer listed if it's a help buffer.  Useful when
         * using CTRL-O to go back to a help file. */
        if (!curbuf->b_help)
            set_buflisted(TRUE);
    }

#ifdef FEAT_AUTOCMD
    /* If autocommands change buffers under our fingers, forget about
     * editing the file. */
    if (buf != curbuf)
        goto theend;
# ifdef FEAT_EVAL
    if (aborting())         /* autocmds may abort script processing */
        goto theend;
# endif

    /* Since we are starting to edit a file, consider the filetype to be
     * unset.  Helps for when an autocommand changes files and expects syntax
     * highlighting to work in the other file. */
    did_filetype = FALSE;
#endif

/*
 * other_file   oldbuf
 *  FALSE       FALSE       re-edit same file, buffer is re-used
 *  FALSE       TRUE        re-edit same file, nothing changes
 *  TRUE        FALSE       start editing new file, new buffer
 *  TRUE        TRUE        start editing in existing buffer (nothing to do)
 */
    if (!other_file && !oldbuf)         /* re-use the buffer */
    {
        set_last_cursor(curwin);        /* may set b_last_cursor */
        if (newlnum == ECMD_LAST || newlnum == ECMD_LASTL)
        {
            newlnum = curwin->w_cursor.lnum;
            solcol = curwin->w_cursor.col;
        }
#ifdef FEAT_AUTOCMD
        buf = curbuf;
        if (buf->b_fname != NULL)
            new_name = vim_strsave(buf->b_fname);
        else
            new_name = NULL;
#endif
        buf_freeall(curbuf, FALSE, FALSE);   /* free all things for buffer */
#ifdef FEAT_AUTOCMD
        /* If autocommands deleted the buffer we were going to re-edit, give
         * up and jump to the end. */
        if (!buf_valid(buf))
        {
            delbuf_msg(new_name);       /* frees new_name */
            goto theend;
        }
        vim_free(new_name);

        /* If autocommands change buffers under our fingers, forget about
         * re-editing the file.  Should do the buf_clear_file(), but perhaps
         * the autocommands changed the buffer... */
        if (buf != curbuf)
            goto theend;
# ifdef FEAT_EVAL
        if (aborting())     /* autocmds may abort script processing */
            goto theend;
# endif
#endif
        buf_clear_file(curbuf);
        curbuf->b_op_start.lnum = 0;    /* clear '[ and '] marks */
        curbuf->b_op_end.lnum = 0;
    }

/*
 * If we get here we are sure to start editing
 */
    /* don't redraw until the cursor is in the right line */
    ++RedrawingDisabled;

    /* Assume success now */
    retval = OK;

    /*
     * Reset cursor position, could be used by autocommands.
     */
    check_cursor();

    /*
     * Check if we are editing the w_arg_idx file in the argument list.
     */
    check_arg_idx(curwin);

#ifdef FEAT_AUTOCMD
    if (!auto_buf)
#endif
    {
        /*
         * Set cursor and init window before reading the file and executing
         * autocommands.  This allows for the autocommands to position the
         * cursor.
         */
        curwin_init();

#ifdef FEAT_FOLDING
        /* It's possible that all lines in the buffer changed.  Need to update
         * automatic folding for all windows where it's used. */
# ifdef FEAT_WINDOWS
        {
            win_T           *win;
            tabpage_T       *tp;

            FOR_ALL_TAB_WINDOWS(tp, win)
                if (win->w_buffer == curbuf)
                    foldUpdateAll(win);
        }
# else
        foldUpdateAll(curwin);
# endif
#endif

        /* Change directories when the 'acd' option is set. */
        DO_AUTOCHDIR

        /*
         * Careful: open_buffer() and apply_autocmds() may change the current
         * buffer and window.
         */
        lnum = curwin->w_cursor.lnum;
        topline = curwin->w_topline;
        if (!oldbuf)                        /* need to read the file */
        {
#if defined(HAS_SWAP_EXISTS_ACTION)
            swap_exists_action = SEA_DIALOG;
#endif
            curbuf->b_flags |= BF_CHECK_RO; /* set/reset 'ro' flag */

            /*
             * Open the buffer and read the file.
             */
#if defined(FEAT_AUTOCMD) && defined(FEAT_EVAL)
            if (should_abort(open_buffer(FALSE, eap)))
                retval = FAIL;
#else
            (void)open_buffer(FALSE, eap);
#endif

#if defined(HAS_SWAP_EXISTS_ACTION)
            if (swap_exists_action == SEA_QUIT)
                retval = FAIL;
            handle_swap_exists(old_curbuf);
#endif
        }
#ifdef FEAT_AUTOCMD
        else
        {
            /* Read the modelines, but only to set window-local options.  Any
             * buffer-local options have already been set and may have been
             * changed by the user. */
            do_modelines(OPT_WINONLY);

            apply_autocmds_retval(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf,
                                                                    &retval);
            apply_autocmds_retval(EVENT_BUFWINENTER, NULL, NULL, FALSE, curbuf,
                                                                    &retval);
        }
        check_arg_idx(curwin);
#endif

        /*
         * If autocommands change the cursor position or topline, we should
         * keep it.
         */
        if (curwin->w_cursor.lnum != lnum)
        {
            newlnum = curwin->w_cursor.lnum;
            newcol = curwin->w_cursor.col;
        }
        if (curwin->w_topline == topline)
            topline = 0;

        /* Even when cursor didn't move we need to recompute topline. */
        changed_line_abv_curs();

#ifdef FEAT_TITLE
        maketitle();
#endif
    }

#ifdef FEAT_DIFF
    /* Tell the diff stuff that this buffer is new and/or needs updating.
     * Also needed when re-editing the same buffer, because unloading will
     * have removed it as a diff buffer. */
    if (curwin->w_p_diff)
    {
        diff_buf_add(curbuf);
        diff_invalidate(curbuf);
    }
#endif

#ifdef FEAT_SPELL
    /* If the window options were changed may need to set the spell language.
     * Can only do this after the buffer has been properly setup. */
    if (did_get_winopts && curwin->w_p_spell && *curbuf->b_p_spl != NUL)
        did_set_spelllang(curbuf);
#endif

    if (command == NULL)
    {
        if (newcol >= 0)        /* position set by autocommands */
        {
            curwin->w_cursor.lnum = newlnum;
            curwin->w_cursor.col = newcol;
            check_cursor();
        }
        else if (newlnum > 0)   /* line number from caller or old position */
        {
            curwin->w_cursor.lnum = newlnum;
            check_cursor_lnum();
            if (solcol >= 0 && !p_sol)
            {
                /* 'sol' is off: Use last known column. */
                curwin->w_cursor.col = solcol;
                check_cursor_col();
#ifdef FEAT_VIRTUALEDIT
                curwin->w_cursor.coladd = 0;
#endif
                curwin->w_set_curswant = TRUE;
            }
            else
                beginline(BL_SOL | BL_FIX);
        }
        else                    /* no line number, go to last line in Ex mode */
        {
            if (exmode_active)
                curwin->w_cursor.lnum = curbuf->b_ml.ml_line_count;
            beginline(BL_WHITE | BL_FIX);
        }
    }

#ifdef FEAT_WINDOWS
    /* Check if cursors in other windows on the same buffer are still valid */
    check_lnums(FALSE);
#endif

    /*
     * Did not read the file, need to show some info about the file.
     * Do this after setting the cursor.
     */
    if (oldbuf
#ifdef FEAT_AUTOCMD
                && !auto_buf
#endif
                            )
    {
        int     msg_scroll_save = msg_scroll;

        /* Obey the 'O' flag in 'cpoptions': overwrite any previous file
         * message. */
        if (shortmess(SHM_OVERALL) && !exiting && p_verbose == 0)
            msg_scroll = FALSE;
        if (!msg_scroll)        /* wait a bit when overwriting an error msg */
            check_for_delay(FALSE);
        msg_start();
        msg_scroll = msg_scroll_save;
        msg_scrolled_ign = TRUE;

        fileinfo(FALSE, TRUE, FALSE);

        msg_scrolled_ign = FALSE;
    }

    if (command != NULL)
        do_cmdline(command, NULL, NULL, DOCMD_VERBOSE);

#ifdef FEAT_KEYMAP
    if (curbuf->b_kmap_state & KEYMAP_INIT)
        keymap_init();
#endif

    --RedrawingDisabled;
    if (!skip_redraw)
    {
        n = p_so;
        if (topline == 0 && command == NULL)
            p_so = 999;                 /* force cursor halfway the window */
        update_topline();
#ifdef FEAT_SCROLLBIND
        curwin->w_scbind_pos = curwin->w_topline;
#endif
        p_so = n;
        redraw_curbuf_later(NOT_VALID); /* redraw this buffer later */
    }

    if (p_im)
        need_start_insertmode = TRUE;

    /* Change directories when the 'acd' option is set. */
    DO_AUTOCHDIR

#if defined(FEAT_SUN_WORKSHOP) || defined(FEAT_NETBEANS_INTG)
    if (gui.in_use && curbuf->b_ffname != NULL)
    {
# ifdef FEAT_SUN_WORKSHOP
        if (usingSunWorkShop)
            workshop_file_opened((char *)curbuf->b_ffname, curbuf->b_p_ro);
# endif
# ifdef FEAT_NETBEANS_INTG
        if (usingNetbeans && ((flags & ECMD_SET_HELP) != ECMD_SET_HELP))
            netbeans_file_opened(curbuf);
# endif
    }
#endif

theend:
#ifdef FEAT_AUTOCMD
    if (did_set_swapcommand)
        set_vim_var_string(VV_SWAPCOMMAND, NULL, -1);
#endif
#ifdef FEAT_BROWSE
    vim_free(browse_file);
#endif
    vim_free(free_fname);
    return retval;
}

#ifdef FEAT_AUTOCMD
    static void
delbuf_msg(name)
    char_u      *name;
{
    EMSG2(_("E143: Autocommands unexpectedly deleted new buffer %s"),
            name == NULL ? (char_u *)"" : name);
    vim_free(name);
    au_new_curbuf = NULL;
}
#endif

static int append_indent = 0;       /* autoindent for first line */

/*
 * ":insert" and ":append", also used by ":change"
 */
    void
ex_append(eap)
    exarg_T     *eap;
{
    char_u      *theline;
    int         did_undo = FALSE;
    linenr_T    lnum = eap->line2;
    int         indent = 0;
    char_u      *p;
    int         vcol;
    int         empty = (curbuf->b_ml.ml_flags & ML_EMPTY);

    /* the ! flag toggles autoindent */
    if (eap->forceit)
        curbuf->b_p_ai = !curbuf->b_p_ai;

    /* First autoindent comes from the line we start on */
    if (eap->cmdidx != CMD_change && curbuf->b_p_ai && lnum > 0)
        append_indent = get_indent_lnum(lnum);

    if (eap->cmdidx != CMD_append)
        --lnum;

    /* when the buffer is empty append to line 0 and delete the dummy line */
    if (empty && lnum == 1)
        lnum = 0;

    State = INSERT;                 /* behave like in Insert mode */
    if (curbuf->b_p_iminsert == B_IMODE_LMAP)
        State |= LANGMAP;

    for (;;)
    {
        msg_scroll = TRUE;
        need_wait_return = FALSE;
        if (curbuf->b_p_ai)
        {
            if (append_indent >= 0)
            {
                indent = append_indent;
                append_indent = -1;
            }
            else if (lnum > 0)
                indent = get_indent_lnum(lnum);
        }
        ex_keep_indent = FALSE;
        if (eap->getline == NULL)
        {
            /* No getline() function, use the lines that follow. This ends
             * when there is no more. */
            if (eap->nextcmd == NULL || *eap->nextcmd == NUL)
                break;
            p = vim_strchr(eap->nextcmd, NL);
            if (p == NULL)
                p = eap->nextcmd + STRLEN(eap->nextcmd);
            theline = vim_strnsave(eap->nextcmd, (int)(p - eap->nextcmd));
            if (*p != NUL)
                ++p;
            eap->nextcmd = p;
        }
        else
            theline = eap->getline(
#ifdef FEAT_EVAL
                    eap->cstack->cs_looplevel > 0 ? -1 :
#endif
                    NUL, eap->cookie, indent);
        lines_left = Rows - 1;
        if (theline == NULL)
            break;

        /* Using ^ CTRL-D in getexmodeline() makes us repeat the indent. */
        if (ex_keep_indent)
            append_indent = indent;

        /* Look for the "." after automatic indent. */
        vcol = 0;
        for (p = theline; indent > vcol; ++p)
        {
            if (*p == ' ')
                ++vcol;
            else if (*p == TAB)
                vcol += 8 - vcol % 8;
            else
                break;
        }
        if ((p[0] == '.' && p[1] == NUL)
                || (!did_undo && u_save(lnum, lnum + 1 + (empty ? 1 : 0))
                                                                     == FAIL))
        {
            vim_free(theline);
            break;
        }

        /* don't use autoindent if nothing was typed. */
        if (p[0] == NUL)
            theline[0] = NUL;

        did_undo = TRUE;
        ml_append(lnum, theline, (colnr_T)0, FALSE);
        appended_lines_mark(lnum, 1L);

        vim_free(theline);
        ++lnum;

        if (empty)
        {
            ml_delete(2L, FALSE);
            empty = FALSE;
        }
    }
    State = NORMAL;

    if (eap->forceit)
        curbuf->b_p_ai = !curbuf->b_p_ai;

    /* "start" is set to eap->line2+1 unless that position is invalid (when
     * eap->line2 pointed to the end of the buffer and nothing was appended)
     * "end" is set to lnum when something has been appended, otherwise
     * it is the same than "start"  -- Acevedo */
    curbuf->b_op_start.lnum = (eap->line2 < curbuf->b_ml.ml_line_count) ?
        eap->line2 + 1 : curbuf->b_ml.ml_line_count;
    if (eap->cmdidx != CMD_append)
        --curbuf->b_op_start.lnum;
    curbuf->b_op_end.lnum = (eap->line2 < lnum)
                                             ? lnum : curbuf->b_op_start.lnum;
    curbuf->b_op_start.col = curbuf->b_op_end.col = 0;
    curwin->w_cursor.lnum = lnum;
    check_cursor_lnum();
    beginline(BL_SOL | BL_FIX);

    need_wait_return = FALSE;   /* don't use wait_return() now */
    ex_no_reprint = TRUE;
}

/*
 * ":change"
 */
    void
ex_change(eap)
    exarg_T     *eap;
{
    linenr_T    lnum;

    if (eap->line2 >= eap->line1
            && u_save(eap->line1 - 1, eap->line2 + 1) == FAIL)
        return;

    /* the ! flag toggles autoindent */
    if (eap->forceit ? !curbuf->b_p_ai : curbuf->b_p_ai)
        append_indent = get_indent_lnum(eap->line1);

    for (lnum = eap->line2; lnum >= eap->line1; --lnum)
    {
        if (curbuf->b_ml.ml_flags & ML_EMPTY)       /* nothing to delete */
            break;
        ml_delete(eap->line1, FALSE);
    }
    deleted_lines_mark(eap->line1, (long)(eap->line2 - lnum));

    /* ":append" on the line above the deleted lines. */
    eap->line2 = eap->line1;
    ex_append(eap);
}

    void
ex_z(eap)
    exarg_T     *eap;
{
    char_u      *x;
    int         bigness;
    char_u      *kind;
    int         minus = 0;
    linenr_T    start, end, curs, i;
    int         j;
    linenr_T    lnum = eap->line2;

    /* Vi compatible: ":z!" uses display height, without a count uses
     * 'scroll' */
    if (eap->forceit)
        bigness = curwin->w_height;
    else if (firstwin == lastwin)
        bigness = curwin->w_p_scr * 2;
    else
        bigness = curwin->w_height - 3;
    if (bigness < 1)
        bigness = 1;

    x = eap->arg;
    kind = x;
    if (*kind == '-' || *kind == '+' || *kind == '='
                                              || *kind == '^' || *kind == '.')
        ++x;
    while (*x == '-' || *x == '+')
        ++x;

    if (*x != 0)
    {
        if (!VIM_ISDIGIT(*x))
        {
            EMSG(_("E144: non-numeric argument to :z"));
            return;
        }
        else
        {
            bigness = atoi((char *)x);
            p_window = bigness;
            if (*kind == '=')
                bigness += 2;
        }
    }

    /* the number of '-' and '+' multiplies the distance */
    if (*kind == '-' || *kind == '+')
        for (x = kind + 1; *x == *kind; ++x)
            ;

    switch (*kind)
    {
        case '-':
            start = lnum - bigness * (linenr_T)(x - kind);
            end = start + bigness;
            curs = end;
            break;

        case '=':
            start = lnum - (bigness + 1) / 2 + 1;
            end = lnum + (bigness + 1) / 2 - 1;
            curs = lnum;
            minus = 1;
            break;

        case '^':
            start = lnum - bigness * 2;
            end = lnum - bigness;
            curs = lnum - bigness;
            break;

        case '.':
            start = lnum - (bigness + 1) / 2 + 1;
            end = lnum + (bigness + 1) / 2 - 1;
            curs = end;
            break;

        default:  /* '+' */
            start = lnum;
            if (*kind == '+')
                start += bigness * (linenr_T)(x - kind - 1) + 1;
            else if (eap->addr_count == 0)
                ++start;
            end = start + bigness - 1;
            curs = end;
            break;
    }

    if (start < 1)
        start = 1;

    if (end > curbuf->b_ml.ml_line_count)
        end = curbuf->b_ml.ml_line_count;

    if (curs > curbuf->b_ml.ml_line_count)
        curs = curbuf->b_ml.ml_line_count;

    for (i = start; i <= end; i++)
    {
        if (minus && i == lnum)
        {
            msg_putchar('\n');

            for (j = 1; j < Columns; j++)
                msg_putchar('-');
        }

        print_line(i, eap->flags & EXFLAG_NR, eap->flags & EXFLAG_LIST);

        if (minus && i == lnum)
        {
            msg_putchar('\n');

            for (j = 1; j < Columns; j++)
                msg_putchar('-');
        }
    }

    curwin->w_cursor.lnum = curs;
    ex_no_reprint = TRUE;
}

/*
 * Check if the restricted flag is set.
 * If so, give an error message and return TRUE.
 * Otherwise, return FALSE.
 */
    int
check_restricted()
{
    if (restricted)
    {
        EMSG(_("E145: Shell commands not allowed in rvim"));
        return TRUE;
    }
    return FALSE;
}

/*
 * Check if the secure flag is set (.exrc or .vimrc in current directory).
 * If so, give an error message and return TRUE.
 * Otherwise, return FALSE.
 */
    int
check_secure()
{
    if (secure)
    {
        secure = 2;
        EMSG(_(e_curdir));
        return TRUE;
    }
#ifdef HAVE_SANDBOX
    /*
     * In the sandbox more things are not allowed, including the things
     * disallowed in secure mode.
     */
    if (sandbox != 0)
    {
        EMSG(_(e_sandbox));
        return TRUE;
    }
#endif
    return FALSE;
}

static char_u   *old_sub = NULL;        /* previous substitute pattern */
static int      global_need_beginline;  /* call beginline() after ":g" */

/* do_sub()
 *
 * Perform a substitution from line eap->line1 to line eap->line2 using the
 * command pointed to by eap->arg which should be of the form:
 *
 * /pattern/substitution/{flags}
 *
 * The usual escapes are supported as described in the regexp docs.
 */
    void
do_sub(eap)
    exarg_T     *eap;
{
    linenr_T    lnum;
    long        i = 0;
    regmmatch_T regmatch;
    static int  do_all = FALSE;         /* do multiple substitutions per line */
    static int  do_ask = FALSE;         /* ask for confirmation */
    static int  do_count = FALSE;       /* count only */
    static int  do_error = TRUE;        /* if false, ignore errors */
    static int  do_print = FALSE;       /* print last line with subs. */
    static int  do_list = FALSE;        /* list last line with subs. */
    static int  do_number = FALSE;      /* list last line with line nr*/
    static int  do_ic = 0;              /* ignore case flag */
    char_u      *pat = NULL, *sub = NULL;       /* init for GCC */
    int         delimiter;
    int         sublen;
    int         got_quit = FALSE;
    int         got_match = FALSE;
    int         temp;
    int         which_pat;
    char_u      *cmd;
    int         save_State;
    linenr_T    first_line = 0;         /* first changed line */
    linenr_T    last_line= 0;           /* below last changed line AFTER the
                                         * change */
    linenr_T    old_line_count = curbuf->b_ml.ml_line_count;
    linenr_T    line2;
    long        nmatch;                 /* number of lines in match */
    char_u      *sub_firstline;         /* allocated copy of first sub line */
    int         endcolumn = FALSE;      /* cursor in last column when done */
    pos_T       old_cursor = curwin->w_cursor;

    cmd = eap->arg;
    if (!global_busy)
    {
        sub_nsubs = 0;
        sub_nlines = 0;
    }

    if (eap->cmdidx == CMD_tilde)
        which_pat = RE_LAST;    /* use last used regexp */
    else
        which_pat = RE_SUBST;   /* use last substitute regexp */

                                /* new pattern and substitution */
    if (eap->cmd[0] == 's' && *cmd != NUL && !vim_iswhite(*cmd)
                && vim_strchr((char_u *)"0123456789cegriIp|\"", *cmd) == NULL)
    {
                                /* don't accept alphanumeric for separator */
        if (isalpha(*cmd))
        {
            EMSG(_("E146: Regular expressions can't be delimited by letters"));
            return;
        }
        /*
         * undocumented vi feature:
         *  "\/sub/" and "\?sub?" use last used search pattern (almost like
         *  //sub/r).  "\&sub&" use last substitute pattern (like //sub/).
         */
        if (*cmd == '\\')
        {
            ++cmd;
            if (vim_strchr((char_u *)"/?&", *cmd) == NULL)
            {
                EMSG(_(e_backslash));
                return;
            }
            if (*cmd != '&')
                which_pat = RE_SEARCH;      /* use last '/' pattern */
            pat = (char_u *)"";             /* empty search pattern */
            delimiter = *cmd++;             /* remember delimiter character */
        }
        else            /* find the end of the regexp */
        {
#ifdef FEAT_FKMAP       /* reverse the flow of the Farsi characters */
            if (p_altkeymap && curwin->w_p_rl)
                lrF_sub(cmd);
#endif
            which_pat = RE_LAST;            /* use last used regexp */
            delimiter = *cmd++;             /* remember delimiter character */
            pat = cmd;                      /* remember start of search pat */
            cmd = skip_regexp(cmd, delimiter, p_magic, &eap->arg);
            if (cmd[0] == delimiter)        /* end delimiter found */
                *cmd++ = NUL;               /* replace it with a NUL */
        }

        /*
         * Small incompatibility: vi sees '\n' as end of the command, but in
         * Vim we want to use '\n' to find/substitute a NUL.
         */
        sub = cmd;          /* remember the start of the substitution */

        while (cmd[0])
        {
            if (cmd[0] == delimiter)            /* end delimiter found */
            {
                *cmd++ = NUL;                   /* replace it with a NUL */
                break;
            }
            if (cmd[0] == '\\' && cmd[1] != 0)  /* skip escaped characters */
                ++cmd;
            mb_ptr_adv(cmd);
        }

        if (!eap->skip)
        {
            /* In POSIX vi ":s/pat/%/" uses the previous subst. string. */
            if (STRCMP(sub, "%") == 0
                                 && vim_strchr(p_cpo, CPO_SUBPERCENT) != NULL)
            {
                if (old_sub == NULL)    /* there is no previous command */
                {
                    EMSG(_(e_nopresub));
                    return;
                }
                sub = old_sub;
            }
            else
            {
                vim_free(old_sub);
                old_sub = vim_strsave(sub);
            }
        }
    }
    else if (!eap->skip)        /* use previous pattern and substitution */
    {
        if (old_sub == NULL)    /* there is no previous command */
        {
            EMSG(_(e_nopresub));
            return;
        }
        pat = NULL;             /* search_regcomp() will use previous pattern */
        sub = old_sub;

        /* Vi compatibility quirk: repeating with ":s" keeps the cursor in the
         * last column after using "$". */
        endcolumn = (curwin->w_curswant == MAXCOL);
    }

    /*
     * Find trailing options.  When '&' is used, keep old options.
     */
    if (*cmd == '&')
        ++cmd;
    else
    {
        if (!p_ed)
        {
            if (p_gd)           /* default is global on */
                do_all = TRUE;
            else
                do_all = FALSE;
            do_ask = FALSE;
        }
        do_error = TRUE;
        do_print = FALSE;
        do_count = FALSE;
        do_number = FALSE;
        do_ic = 0;
    }
    while (*cmd)
    {
        /*
         * Note that 'g' and 'c' are always inverted, also when p_ed is off.
         * 'r' is never inverted.
         */
        if (*cmd == 'g')
            do_all = !do_all;
        else if (*cmd == 'c')
            do_ask = !do_ask;
        else if (*cmd == 'n')
            do_count = TRUE;
        else if (*cmd == 'e')
            do_error = !do_error;
        else if (*cmd == 'r')       /* use last used regexp */
            which_pat = RE_LAST;
        else if (*cmd == 'p')
            do_print = TRUE;
        else if (*cmd == '#')
        {
            do_print = TRUE;
            do_number = TRUE;
        }
        else if (*cmd == 'l')
        {
            do_print = TRUE;
            do_list = TRUE;
        }
        else if (*cmd == 'i')       /* ignore case */
            do_ic = 'i';
        else if (*cmd == 'I')       /* don't ignore case */
            do_ic = 'I';
        else
            break;
        ++cmd;
    }
    if (do_count)
        do_ask = FALSE;

    /*
     * check for a trailing count
     */
    cmd = skipwhite(cmd);
    if (VIM_ISDIGIT(*cmd))
    {
        i = getdigits(&cmd);
        if (i <= 0 && !eap->skip && do_error)
        {
            EMSG(_(e_zerocount));
            return;
        }
        eap->line1 = eap->line2;
        eap->line2 += i - 1;
        if (eap->line2 > curbuf->b_ml.ml_line_count)
            eap->line2 = curbuf->b_ml.ml_line_count;
    }

    /*
     * check for trailing command or garbage
     */
    cmd = skipwhite(cmd);
    if (*cmd && *cmd != '"')        /* if not end-of-line or comment */
    {
        eap->nextcmd = check_nextcmd(cmd);
        if (eap->nextcmd == NULL)
        {
            EMSG(_(e_trailing));
            return;
        }
    }

    if (eap->skip)          /* not executing commands, only parsing */
        return;

    if (!do_count && !curbuf->b_p_ma)
    {
        /* Substitution is not allowed in non-'modifiable' buffer */
        EMSG(_(e_modifiable));
        return;
    }

    if (search_regcomp(pat, RE_SUBST, which_pat, SEARCH_HIS, &regmatch) == FAIL)
    {
        if (do_error)
            EMSG(_(e_invcmd));
        return;
    }

    /* the 'i' or 'I' flag overrules 'ignorecase' and 'smartcase' */
    if (do_ic == 'i')
        regmatch.rmm_ic = TRUE;
    else if (do_ic == 'I')
        regmatch.rmm_ic = FALSE;

    sub_firstline = NULL;

    /*
     * ~ in the substitute pattern is replaced with the old pattern.
     * We do it here once to avoid it to be replaced over and over again.
     * But don't do it when it starts with "\=", then it's an expression.
     */
    if (!(sub[0] == '\\' && sub[1] == '='))
        sub = regtilde(sub, p_magic);

    /*
     * Check for a match on each line.
     */
    line2 = eap->line2;
    for (lnum = eap->line1; lnum <= line2 && !(got_quit
#if defined(FEAT_EVAL) && defined(FEAT_AUTOCMD)
                || aborting()
#endif
                ); ++lnum)
    {
        nmatch = vim_regexec_multi(&regmatch, curwin, curbuf, lnum,
                                                            (colnr_T)0, NULL);
        if (nmatch)
        {
            colnr_T     copycol;
            colnr_T     matchcol;
            colnr_T     prev_matchcol = MAXCOL;
            char_u      *new_end, *new_start = NULL;
            unsigned    new_start_len = 0;
            char_u      *p1;
            int         did_sub = FALSE;
            int         lastone;
            unsigned    len, needed_len;
            long        nmatch_tl = 0;  /* nr of lines matched below lnum */
            int         do_again;       /* do it again after joining lines */
            int         skip_match = FALSE;
            linenr_T    sub_firstlnum;  /* nr of first sub line */

            /*
             * The new text is build up step by step, to avoid too much
             * copying.  There are these pieces:
             * sub_firstline    The old text, unmodified.
             * copycol          Column in the old text where we started
             *                  looking for a match; from here old text still
             *                  needs to be copied to the new text.
             * matchcol         Column number of the old text where to look
             *                  for the next match.  It's just after the
             *                  previous match or one further.
             * prev_matchcol    Column just after the previous match (if any).
             *                  Mostly equal to matchcol, except for the first
             *                  match and after skipping an empty match.
             * regmatch.*pos    Where the pattern matched in the old text.
             * new_start        The new text, all that has been produced so
             *                  far.
             * new_end          The new text, where to append new text.
             *
             * lnum             The line number where we found the start of
             *                  the match.  Can be below the line we searched
             *                  when there is a \n before a \zs in the
             *                  pattern.
             * sub_firstlnum    The line number in the buffer where to look
             *                  for a match.  Can be different from "lnum"
             *                  when the pattern or substitute string contains
             *                  line breaks.
             *
             * Special situations:
             * - When the substitute string contains a line break, the part up
             *   to the line break is inserted in the text, but the copy of
             *   the original line is kept.  "sub_firstlnum" is adjusted for
             *   the inserted lines.
             * - When the matched pattern contains a line break, the old line
             *   is taken from the line at the end of the pattern.  The lines
             *   in the match are deleted later, "sub_firstlnum" is adjusted
             *   accordingly.
             *
             * The new text is built up in new_start[].  It has some extra
             * room to avoid using alloc()/free() too often.  new_start_len is
             * the length of the allocated memory at new_start.
             *
             * Make a copy of the old line, so it won't be taken away when
             * updating the screen or handling a multi-line match.  The "old_"
             * pointers point into this copy.
             */
            sub_firstlnum = lnum;
            copycol = 0;
            matchcol = 0;

            /* At first match, remember current cursor position. */
            if (!got_match)
            {
                setpcmark();
                got_match = TRUE;
            }

            /*
             * Loop until nothing more to replace in this line.
             * 1. Handle match with empty string.
             * 2. If do_ask is set, ask for confirmation.
             * 3. substitute the string.
             * 4. if do_all is set, find next match
             * 5. break if there isn't another match in this line
             */
            for (;;)
            {
                /* Advance "lnum" to the line where the match starts.  The
                 * match does not start in the first line when there is a line
                 * break before \zs. */
                if (regmatch.startpos[0].lnum > 0)
                {
                    lnum += regmatch.startpos[0].lnum;
                    sub_firstlnum += regmatch.startpos[0].lnum;
                    nmatch -= regmatch.startpos[0].lnum;
                    vim_free(sub_firstline);
                    sub_firstline = NULL;
                }

                if (sub_firstline == NULL)
                {
                    sub_firstline = vim_strsave(ml_get(sub_firstlnum));
                    if (sub_firstline == NULL)
                    {
                        vim_free(new_start);
                        goto outofmem;
                    }
                }

                /* Save the line number of the last change for the final
                 * cursor position (just like Vi). */
                curwin->w_cursor.lnum = lnum;
                do_again = FALSE;

                /*
                 * 1. Match empty string does not count, except for first
                 * match.  This reproduces the strange vi behaviour.
                 * This also catches endless loops.
                 */
                if (matchcol == prev_matchcol
                        && regmatch.endpos[0].lnum == 0
                        && matchcol == regmatch.endpos[0].col)
                {
                    if (sub_firstline[matchcol] == NUL)
                        /* We already were at the end of the line.  Don't look
                         * for a match in this line again. */
                        skip_match = TRUE;
                    else
                        ++matchcol; /* search for a match at next column */
                    goto skip;
                }

                /* Normally we continue searching for a match just after the
                 * previous match. */
                matchcol = regmatch.endpos[0].col;
                prev_matchcol = matchcol;

                /*
                 * 2. If do_count is set only increase the counter.
                 *    If do_ask is set, ask for confirmation.
                 */
                if (do_count)
                {
                    /* For a multi-line match, put matchcol at the NUL at
                     * the end of the line and set nmatch to one, so that
                     * we continue looking for a match on the next line.
                     * Avoids that ":s/\nB\@=//gc" get stuck. */
                    if (nmatch > 1)
                    {
                        matchcol = (colnr_T)STRLEN(sub_firstline);
                        nmatch = 1;
                        skip_match = TRUE;
                    }
                    sub_nsubs++;
                    did_sub = TRUE;
                    goto skip;
                }

                if (do_ask)
                {
                    /* change State to CONFIRM, so that the mouse works
                     * properly */
                    save_State = State;
                    State = CONFIRM;
#ifdef FEAT_MOUSE
                    setmouse();         /* disable mouse in xterm */
#endif
                    curwin->w_cursor.col = regmatch.startpos[0].col;

                    /* When 'cpoptions' contains "u" don't sync undo when
                     * asking for confirmation. */
                    if (vim_strchr(p_cpo, CPO_UNDO) != NULL)
                        ++no_u_sync;

                    /*
                     * Loop until 'y', 'n', 'q', CTRL-E or CTRL-Y typed.
                     */
                    while (do_ask)
                    {
                        if (exmode_active)
                        {
                            char_u      *resp;
                            colnr_T     sc, ec;

                            print_line_no_prefix(lnum, FALSE, FALSE);

                            getvcol(curwin, &curwin->w_cursor, &sc, NULL, NULL);
                            curwin->w_cursor.col = regmatch.endpos[0].col - 1;
                            getvcol(curwin, &curwin->w_cursor, NULL, NULL, &ec);
                            msg_start();
                            for (i = 0; i < (long)sc; ++i)
                                msg_putchar(' ');
                            for ( ; i <= (long)ec; ++i)
                                msg_putchar('^');

                            resp = getexmodeline('?', NULL, 0);
                            if (resp != NULL)
                            {
                                i = *resp;
                                vim_free(resp);
                            }
                        }
                        else
                        {
#ifdef FEAT_FOLDING
                            int save_p_fen = curwin->w_p_fen;

                            curwin->w_p_fen = FALSE;
#endif
                            /* Invert the matched string.
                             * Remove the inversion afterwards. */
                            temp = RedrawingDisabled;
                            RedrawingDisabled = 0;

                            search_match_lines = regmatch.endpos[0].lnum
                                                  - regmatch.startpos[0].lnum;
                            search_match_endcol = regmatch.endpos[0].col;
                            highlight_match = TRUE;

                            update_topline();
                            validate_cursor();
                            update_screen(SOME_VALID);
                            highlight_match = FALSE;
                            redraw_later(SOME_VALID);

#ifdef FEAT_FOLDING
                            curwin->w_p_fen = save_p_fen;
#endif
                            if (msg_row == Rows - 1)
                                msg_didout = FALSE;     /* avoid a scroll-up */
                            msg_starthere();
                            i = msg_scroll;
                            msg_scroll = 0;             /* truncate msg when
                                                           needed */
                            msg_no_more = TRUE;
                            /* write message same highlighting as for
                             * wait_return */
                            smsg_attr(hl_attr(HLF_R),
                                    (char_u *)_("replace with %s (y/n/a/q/l/^E/^Y)?"), sub);
                            msg_no_more = FALSE;
                            msg_scroll = i;
                            showruler(TRUE);
                            windgoto(msg_row, msg_col);
                            RedrawingDisabled = temp;

#ifdef USE_ON_FLY_SCROLL
                            dont_scroll = FALSE; /* allow scrolling here */
#endif
                            ++no_mapping;       /* don't map this key */
                            ++allow_keys;       /* allow special keys */
                            i = plain_vgetc();
                            --allow_keys;
                            --no_mapping;

                            /* clear the question */
                            msg_didout = FALSE; /* don't scroll up */
                            msg_col = 0;
                            gotocmdline(TRUE);
                        }

                        need_wait_return = FALSE; /* no hit-return prompt */
                        if (i == 'q' || i == ESC || i == Ctrl_C
#ifdef UNIX
                                || i == intr_char
#endif
                                )
                        {
                            got_quit = TRUE;
                            break;
                        }
                        if (i == 'n')
                            break;
                        if (i == 'y')
                            break;
                        if (i == 'l')
                        {
                            /* last: replace and then stop */
                            do_all = FALSE;
                            line2 = lnum;
                            break;
                        }
                        if (i == 'a')
                        {
                            do_ask = FALSE;
                            break;
                        }
#ifdef FEAT_INS_EXPAND
                        if (i == Ctrl_E)
                            scrollup_clamp();
                        else if (i == Ctrl_Y)
                            scrolldown_clamp();
#endif
                    }
                    State = save_State;
#ifdef FEAT_MOUSE
                    setmouse();
#endif
                    if (vim_strchr(p_cpo, CPO_UNDO) != NULL)
                        --no_u_sync;

                    if (i == 'n')
                    {
                        /* For a multi-line match, put matchcol at the NUL at
                         * the end of the line and set nmatch to one, so that
                         * we continue looking for a match on the next line.
                         * Avoids that ":%s/\nB\@=//gc" and ":%s/\n/,\r/gc"
                         * get stuck when pressing 'n'. */
                        if (nmatch > 1)
                        {
                            matchcol = (colnr_T)STRLEN(sub_firstline);
                            skip_match = TRUE;
                        }
                        goto skip;
                    }
                    if (got_quit)
                        break;
                }

                /* Move the cursor to the start of the match, so that we can
                 * use "\=col("."). */
                curwin->w_cursor.col = regmatch.startpos[0].col;

                /*
                 * 3. substitute the string.
                 */
                /* get length of substitution part */
                sublen = vim_regsub_multi(&regmatch,
                                    sub_firstlnum - regmatch.startpos[0].lnum,
                                    sub, sub_firstline, FALSE, p_magic, TRUE);

                /* When the match included the "$" of the last line it may
                 * go beyond the last line of the buffer. */
                if (nmatch > curbuf->b_ml.ml_line_count - sub_firstlnum + 1)
                {
                    nmatch = curbuf->b_ml.ml_line_count - sub_firstlnum + 1;
                    skip_match = TRUE;
                }

                /* Need room for:
                 * - result so far in new_start (not for first sub in line)
                 * - original text up to match
                 * - length of substituted part
                 * - original text after match
                 */
                if (nmatch == 1)
                    p1 = sub_firstline;
                else
                {
                    p1 = ml_get(sub_firstlnum + nmatch - 1);
                    nmatch_tl += nmatch - 1;
                }
                i = regmatch.startpos[0].col - copycol;
                needed_len = i + ((unsigned)STRLEN(p1) - regmatch.endpos[0].col)
                                                                 + sublen + 1;
                if (new_start == NULL)
                {
                    /*
                     * Get some space for a temporary buffer to do the
                     * substitution into (and some extra space to avoid
                     * too many calls to alloc()/free()).
                     */
                    new_start_len = needed_len + 50;
                    if ((new_start = alloc_check(new_start_len)) == NULL)
                        goto outofmem;
                    *new_start = NUL;
                    new_end = new_start;
                }
                else
                {
                    /*
                     * Check if the temporary buffer is long enough to do the
                     * substitution into.  If not, make it larger (with a bit
                     * extra to avoid too many calls to alloc()/free()).
                     */
                    len = (unsigned)STRLEN(new_start);
                    needed_len += len;
                    if (needed_len > new_start_len)
                    {
                        new_start_len = needed_len + 50;
                        if ((p1 = alloc_check(new_start_len)) == NULL)
                        {
                            vim_free(new_start);
                            goto outofmem;
                        }
                        mch_memmove(p1, new_start, (size_t)(len + 1));
                        vim_free(new_start);
                        new_start = p1;
                    }
                    new_end = new_start + len;
                }

                /*
                 * copy the text up to the part that matched
                 */
                mch_memmove(new_end, sub_firstline + copycol, (size_t)i);
                new_end += i;

                (void)vim_regsub_multi(&regmatch,
                                    sub_firstlnum - regmatch.startpos[0].lnum,
                                           sub, new_end, TRUE, p_magic, TRUE);
                sub_nsubs++;
                did_sub = TRUE;

                /* Move the cursor to the start of the line, to avoid that it
                 * is beyond the end of the line after the substitution. */
                curwin->w_cursor.col = 0;

                /* For a multi-line match, make a copy of the last matched
                 * line and continue in that one. */
                if (nmatch > 1)
                {
                    sub_firstlnum += nmatch - 1;
                    vim_free(sub_firstline);
                    sub_firstline = vim_strsave(ml_get(sub_firstlnum));
                    /* When going beyond the last line, stop substituting. */
                    if (sub_firstlnum <= line2)
                        do_again = TRUE;
                    else
                        do_all = FALSE;
                }

                /* Remember next character to be copied. */
                copycol = regmatch.endpos[0].col;

                if (skip_match)
                {
                    /* Already hit end of the buffer, sub_firstlnum is one
                     * less than what it ought to be. */
                    vim_free(sub_firstline);
                    sub_firstline = vim_strsave((char_u *)"");
                    copycol = 0;
                }

                /*
                 * Now the trick is to replace CTRL-M chars with a real line
                 * break.  This would make it impossible to insert a CTRL-M in
                 * the text.  The line break can be avoided by preceding the
                 * CTRL-M with a backslash.  To be able to insert a backslash,
                 * they must be doubled in the string and are halved here.
                 * That is Vi compatible.
                 */
                for (p1 = new_end; *p1; ++p1)
                {
                    if (p1[0] == '\\' && p1[1] != NUL)  /* remove backslash */
                        STRMOVE(p1, p1 + 1);
                    else if (*p1 == CAR)
                    {
                        if (u_inssub(lnum) == OK)   /* prepare for undo */
                        {
                            *p1 = NUL;              /* truncate up to the CR */
                            ml_append(lnum - 1, new_start,
                                        (colnr_T)(p1 - new_start + 1), FALSE);
                            mark_adjust(lnum + 1, (linenr_T)MAXLNUM, 1L, 0L);
                            if (do_ask)
                                appended_lines(lnum - 1, 1L);
                            else
                            {
                                if (first_line == 0)
                                    first_line = lnum;
                                last_line = lnum + 1;
                            }
                            /* All line numbers increase. */
                            ++sub_firstlnum;
                            ++lnum;
                            ++line2;
                            /* move the cursor to the new line, like Vi */
                            ++curwin->w_cursor.lnum;
                            /* copy the rest */
                            STRMOVE(new_start, p1 + 1);
                            p1 = new_start - 1;
                        }
                    }
#ifdef FEAT_MBYTE
                    else if (has_mbyte)
                        p1 += (*mb_ptr2len)(p1) - 1;
#endif
                }

                /*
                 * 4. If do_all is set, find next match.
                 * Prevent endless loop with patterns that match empty
                 * strings, e.g. :s/$/pat/g or :s/[a-z]* /(&)/g.
                 * But ":s/\n/#/" is OK.
                 */
skip:
                /* We already know that we did the last subst when we are at
                 * the end of the line, except that a pattern like
                 * "bar\|\nfoo" may match at the NUL.  "lnum" can be below
                 * "line2" when there is a \zs in the pattern after a line
                 * break. */
                lastone = (skip_match
                        || got_int
                        || got_quit
                        || lnum > line2
                        || !(do_all || do_again)
                        || (sub_firstline[matchcol] == NUL && nmatch <= 1
                                         && !re_multiline(regmatch.regprog)));
                nmatch = -1;

                /*
                 * Replace the line in the buffer when needed.  This is
                 * skipped when there are more matches.
                 * The check for nmatch_tl is needed for when multi-line
                 * matching must replace the lines before trying to do another
                 * match, otherwise "\@<=" won't work.
                 * When asking the user we like to show the already replaced
                 * text, but don't do it when "\<@=" or "\<@!" is used, it
                 * changes what matches.
                 * When the match starts below where we start searching also
                 * need to replace the line first (using \zs after \n).
                 */
                if (lastone
                        || (do_ask && !re_lookbehind(regmatch.regprog))
                        || nmatch_tl > 0
                        || (nmatch = vim_regexec_multi(&regmatch, curwin,
                                                        curbuf, sub_firstlnum,
                                                         matchcol, NULL)) == 0
                        || regmatch.startpos[0].lnum > 0)
                {
                    if (new_start != NULL)
                    {
                        /*
                         * Copy the rest of the line, that didn't match.
                         * "matchcol" has to be adjusted, we use the end of
                         * the line as reference, because the substitute may
                         * have changed the number of characters.  Same for
                         * "prev_matchcol".
                         */
                        STRCAT(new_start, sub_firstline + copycol);
                        matchcol = (colnr_T)STRLEN(sub_firstline) - matchcol;
                        prev_matchcol = (colnr_T)STRLEN(sub_firstline)
                                                              - prev_matchcol;

                        if (u_savesub(lnum) != OK)
                            break;
                        ml_replace(lnum, new_start, TRUE);

                        if (nmatch_tl > 0)
                        {
                            /*
                             * Matched lines have now been substituted and are
                             * useless, delete them.  The part after the match
                             * has been appended to new_start, we don't need
                             * it in the buffer.
                             */
                            ++lnum;
                            if (u_savedel(lnum, nmatch_tl) != OK)
                                break;
                            for (i = 0; i < nmatch_tl; ++i)
                                ml_delete(lnum, (int)FALSE);
                            mark_adjust(lnum, lnum + nmatch_tl - 1,
                                                   (long)MAXLNUM, -nmatch_tl);
                            if (do_ask)
                                deleted_lines(lnum, nmatch_tl);
                            --lnum;
                            line2 -= nmatch_tl; /* nr of lines decreases */
                            nmatch_tl = 0;
                        }

                        /* When asking, undo is saved each time, must also set
                         * changed flag each time. */
                        if (do_ask)
                            changed_bytes(lnum, 0);
                        else
                        {
                            if (first_line == 0)
                                first_line = lnum;
                            last_line = lnum + 1;
                        }

                        sub_firstlnum = lnum;
                        vim_free(sub_firstline);    /* free the temp buffer */
                        sub_firstline = new_start;
                        new_start = NULL;
                        matchcol = (colnr_T)STRLEN(sub_firstline) - matchcol;
                        prev_matchcol = (colnr_T)STRLEN(sub_firstline)
                                                              - prev_matchcol;
                        copycol = 0;
                    }
                    if (nmatch == -1 && !lastone)
                        nmatch = vim_regexec_multi(&regmatch, curwin, curbuf,
                                               sub_firstlnum, matchcol, NULL);

                    /*
                     * 5. break if there isn't another match in this line
                     */
                    if (nmatch <= 0)
                    {
                        /* If the match found didn't start where we were
                         * searching, do the next search in the line where we
                         * found the match. */
                        if (nmatch == -1)
                            lnum -= regmatch.startpos[0].lnum;
                        break;
                    }
                }

                line_breakcheck();
            }

            if (did_sub)
                ++sub_nlines;
            vim_free(new_start);        /* for when substitute was cancelled */
            vim_free(sub_firstline);    /* free the copy of the original line */
            sub_firstline = NULL;
        }

        line_breakcheck();
    }

    if (first_line != 0)
    {
        /* Need to subtract the number of added lines from "last_line" to get
         * the line number before the change (same as adding the number of
         * deleted lines). */
        i = curbuf->b_ml.ml_line_count - old_line_count;
        changed_lines(first_line, 0, last_line - i, i);
    }

outofmem:
    vim_free(sub_firstline); /* may have to free allocated copy of the line */

    /* ":s/pat//n" doesn't move the cursor */
    if (do_count)
        curwin->w_cursor = old_cursor;

    if (sub_nsubs)
    {
        /* Set the '[ and '] marks. */
        curbuf->b_op_start.lnum = eap->line1;
        curbuf->b_op_end.lnum = line2;
        curbuf->b_op_start.col = curbuf->b_op_end.col = 0;

        if (!global_busy)
        {
            if (endcolumn)
                coladvance((colnr_T)MAXCOL);
            else
                beginline(BL_WHITE | BL_FIX);
            if (!do_sub_msg(do_count) && do_ask)
                MSG("");
        }
        else
            global_need_beginline = TRUE;
        if (do_print)
            print_line(curwin->w_cursor.lnum, do_number, do_list);
    }
    else if (!global_busy)
    {
        if (got_int)            /* interrupted */
            EMSG(_(e_interr));
        else if (got_match)     /* did find something but nothing substituted */
            MSG("");
        else if (do_error)      /* nothing found */
            EMSG2(_(e_patnotf2), get_search_pat());
    }

    vim_free(regmatch.regprog);
}

/*
 * Give message for number of substitutions.
 * Can also be used after a ":global" command.
 * Return TRUE if a message was given.
 */
    int
do_sub_msg(count_only)
    int     count_only;         /* used 'n' flag for ":s" */
{
    int     len = 0;

    /*
     * Only report substitutions when:
     * - more than 'report' substitutions
     * - command was typed by user, or number of changed lines > 'report'
     * - giving messages is not disabled by 'lazyredraw'
     */
    if (((sub_nsubs > p_report && (KeyTyped || sub_nlines > 1 || p_report < 1))
                || count_only)
            && messaging())
    {
        if (got_int)
        {
            STRCPY(msg_buf, _("(Interrupted) "));
            len = (int)STRLEN(msg_buf);
        }
        if (sub_nsubs == 1)
            vim_snprintf((char *)msg_buf + len, sizeof(msg_buf) - len,
                    "%s", count_only ? _("1 match") : _("1 substitution"));
        else
            vim_snprintf((char *)msg_buf + len, sizeof(msg_buf) - len,
                    count_only ? _("%ld matches") : _("%ld substitutions"),
                                                                   sub_nsubs);
        len = (int)STRLEN(msg_buf);
        if (sub_nlines == 1)
            vim_snprintf((char *)msg_buf + len, sizeof(msg_buf) - len,
                    "%s", _(" on 1 line"));
        else
            vim_snprintf((char *)msg_buf + len, sizeof(msg_buf) - len,
                    _(" on %ld lines"), (long)sub_nlines);
        if (msg(msg_buf))
            /* save message to display it after redraw */
            set_keep_msg(msg_buf, 0);
        return TRUE;
    }
    if (got_int)
    {
        EMSG(_(e_interr));
        return TRUE;
    }
    return FALSE;
}

/*
 * Execute a global command of the form:
 *
 * g/pattern/X : execute X on all lines where pattern matches
 * v/pattern/X : execute X on all lines where pattern does not match
 *
 * where 'X' is an EX command
 *
 * The command character (as well as the trailing slash) is optional, and
 * is assumed to be 'p' if missing.
 *
 * This is implemented in two passes: first we scan the file for the pattern and
 * set a mark for each line that (not) matches. secondly we execute the command
 * for each line that has a mark. This is required because after deleting
 * lines we do not know where to search for the next match.
 */
    void
ex_global(eap)
    exarg_T     *eap;
{
    linenr_T    lnum;           /* line number according to old situation */
    int         ndone = 0;
    int         type;           /* first char of cmd: 'v' or 'g' */
    char_u      *cmd;           /* command argument */

    char_u      delim;          /* delimiter, normally '/' */
    char_u      *pat;
    regmmatch_T regmatch;
    int         match;
    int         which_pat;

    if (global_busy)
    {
        EMSG(_("E147: Cannot do :global recursive"));   /* will increment global_busy */
        return;
    }

    if (eap->forceit)               /* ":global!" is like ":vglobal" */
        type = 'v';
    else
        type = *eap->cmd;
    cmd = eap->arg;
    which_pat = RE_LAST;            /* default: use last used regexp */
    sub_nsubs = 0;
    sub_nlines = 0;

    /*
     * undocumented vi feature:
     *  "\/" and "\?": use previous search pattern.
     *           "\&": use previous substitute pattern.
     */
    if (*cmd == '\\')
    {
        ++cmd;
        if (vim_strchr((char_u *)"/?&", *cmd) == NULL)
        {
            EMSG(_(e_backslash));
            return;
        }
        if (*cmd == '&')
            which_pat = RE_SUBST;       /* use previous substitute pattern */
        else
            which_pat = RE_SEARCH;      /* use previous search pattern */
        ++cmd;
        pat = (char_u *)"";
    }
    else if (*cmd == NUL)
    {
        EMSG(_("E148: Regular expression missing from global"));
        return;
    }
    else
    {
        delim = *cmd;           /* get the delimiter */
        if (delim)
            ++cmd;              /* skip delimiter if there is one */
        pat = cmd;              /* remember start of pattern */
        cmd = skip_regexp(cmd, delim, p_magic, &eap->arg);
        if (cmd[0] == delim)                /* end delimiter found */
            *cmd++ = NUL;                   /* replace it with a NUL */
    }

#ifdef FEAT_FKMAP       /* when in Farsi mode, reverse the character flow */
    if (p_altkeymap && curwin->w_p_rl)
        lrFswap(pat,0);
#endif

    if (search_regcomp(pat, RE_BOTH, which_pat, SEARCH_HIS, &regmatch) == FAIL)
    {
        EMSG(_(e_invcmd));
        return;
    }

    /*
     * pass 1: set marks for each (not) matching line
     */
    for (lnum = eap->line1; lnum <= eap->line2 && !got_int; ++lnum)
    {
        /* a match on this line? */
        match = vim_regexec_multi(&regmatch, curwin, curbuf, lnum,
                                                            (colnr_T)0, NULL);
        if ((type == 'g' && match) || (type == 'v' && !match))
        {
            ml_setmarked(lnum);
            ndone++;
        }
        line_breakcheck();
    }

    /*
     * pass 2: execute the command for each line that has been marked
     */
    if (got_int)
        MSG(_(e_interr));
    else if (ndone == 0)
    {
        if (type == 'v')
            smsg((char_u *)_("Pattern found in every line: %s"), pat);
        else
            smsg((char_u *)_(e_patnotf2), pat);
    }
    else
        global_exe(cmd);

    ml_clearmarked();      /* clear rest of the marks */
    vim_free(regmatch.regprog);
}

/*
 * Execute "cmd" on lines marked with ml_setmarked().
 */
    void
global_exe(cmd)
    char_u      *cmd;
{
    linenr_T    old_lcount;     /* b_ml.ml_line_count before the command */
    linenr_T    lnum;           /* line number according to old situation */

    /*
     * Set current position only once for a global command.
     * If global_busy is set, setpcmark() will not do anything.
     * If there is an error, global_busy will be incremented.
     */
    setpcmark();

    /* When the command writes a message, don't overwrite the command. */
    msg_didout = TRUE;

    global_need_beginline = FALSE;
    global_busy = 1;
    old_lcount = curbuf->b_ml.ml_line_count;
    while (!got_int && (lnum = ml_firstmarked()) != 0 && global_busy == 1)
    {
        curwin->w_cursor.lnum = lnum;
        curwin->w_cursor.col = 0;
        if (*cmd == NUL || *cmd == '\n')
            do_cmdline((char_u *)"p", NULL, NULL, DOCMD_NOWAIT);
        else
            do_cmdline(cmd, NULL, NULL, DOCMD_NOWAIT);
        ui_breakcheck();
    }

    global_busy = 0;
    if (global_need_beginline)
        beginline(BL_WHITE | BL_FIX);
    else
        check_cursor(); /* cursor may be beyond the end of the line */

    /* the cursor may not have moved in the text but a change in a previous
     * line may move it on the screen */
    changed_line_abv_curs();

    /* If it looks like no message was written, allow overwriting the
     * command with the report for number of changes. */
    if (msg_col == 0 && msg_scrolled == 0)
        msg_didout = FALSE;

    /* If substitutes done, report number of substitutes, otherwise report
     * number of extra or deleted lines. */
    if (!do_sub_msg(FALSE))
        msgmore(curbuf->b_ml.ml_line_count - old_lcount);
}

#ifdef FEAT_VIMINFO
    int
read_viminfo_sub_string(virp, force)
    vir_T       *virp;
    int         force;
{
    if (old_sub != NULL && force)
        vim_free(old_sub);
    if (force || old_sub == NULL)
        old_sub = viminfo_readstring(virp, 1, TRUE);
    return viminfo_readline(virp);
}

    void
write_viminfo_sub_string(fp)
    FILE    *fp;
{
    if (get_viminfo_parameter('/') != 0 && old_sub != NULL)
    {
        fprintf(fp, _("\n# Last Substitute String:\n$"));
        viminfo_writestring(fp, old_sub);
    }
}
#endif /* FEAT_VIMINFO */

#if defined(EXITFREE) || defined(PROTO)
    void
free_old_sub()
{
    vim_free(old_sub);
}
#endif

#if (defined(FEAT_WINDOWS) && defined(FEAT_QUICKFIX)) || defined(PROTO)
/*
 * Set up for a tagpreview.
 * Return TRUE when it was created.
 */
    int
prepare_tagpreview(undo_sync)
    int         undo_sync;      /* sync undo when leaving the window */
{
    win_T       *wp;

# ifdef FEAT_GUI
    need_mouse_correct = TRUE;
# endif

    /*
     * If there is already a preview window open, use that one.
     */
    if (!curwin->w_p_pvw)
    {
        for (wp = firstwin; wp != NULL; wp = wp->w_next)
            if (wp->w_p_pvw)
                break;
        if (wp != NULL)
            win_enter(wp, undo_sync);
        else
        {
            /*
             * There is no preview window open yet.  Create one.
             */
            if (win_split(g_do_tagpreview > 0 ? g_do_tagpreview : 0, 0)
                                                                      == FAIL)
                return FALSE;
            curwin->w_p_pvw = TRUE;
            curwin->w_p_wfh = TRUE;
# ifdef FEAT_SCROLLBIND
            curwin->w_p_scb = FALSE;        /* don't take over 'scrollbind' */
# endif
# ifdef FEAT_DIFF
            curwin->w_p_diff = FALSE;       /* no 'diff' */
# endif
# ifdef FEAT_FOLDING
            curwin->w_p_fdc = 0;            /* no 'foldcolumn' */
# endif
            return TRUE;
        }
    }
    return FALSE;
}

#endif


/*
 * ":help": open a read-only window on a help file
 */
    void
ex_help(eap)
    exarg_T     *eap;
{
    char_u      *arg;
    char_u      *tag;
    FILE        *helpfd;        /* file descriptor of help file */
    int         n;
    int         i;
#ifdef FEAT_WINDOWS
    win_T       *wp;
#endif
    int         num_matches;
    char_u      **matches;
    char_u      *p;
    int         empty_fnum = 0;
    int         alt_fnum = 0;
    buf_T       *buf;
#ifdef FEAT_MULTI_LANG
    int         len;
    char_u      *lang;
#endif

    if (eap != NULL)
    {
        /*
         * A ":help" command ends at the first LF, or at a '|' that is
         * followed by some text.  Set nextcmd to the following command.
         */
        for (arg = eap->arg; *arg; ++arg)
        {
            if (*arg == '\n' || *arg == '\r'
                    || (*arg == '|' && arg[1] != NUL && arg[1] != '|'))
            {
                *arg++ = NUL;
                eap->nextcmd = arg;
                break;
            }
        }
        arg = eap->arg;

        if (eap->forceit && *arg == NUL)
        {
            EMSG(_("E478: Don't panic!"));
            return;
        }

        if (eap->skip)      /* not executing commands */
            return;
    }
    else
        arg = (char_u *)"";

    /* remove trailing blanks */
    p = arg + STRLEN(arg) - 1;
    while (p > arg && vim_iswhite(*p) && p[-1] != '\\')
        *p-- = NUL;

#ifdef FEAT_MULTI_LANG
    /* Check for a specified language */
    lang = check_help_lang(arg);
#endif

    /* When no argument given go to the index. */
    if (*arg == NUL)
        arg = (char_u *)"help.txt";

    /*
     * Check if there is a match for the argument.
     */
    n = find_help_tags(arg, &num_matches, &matches,
                                                 eap != NULL && eap->forceit);

    i = 0;
#ifdef FEAT_MULTI_LANG
    if (n != FAIL && lang != NULL)
        /* Find first item with the requested language. */
        for (i = 0; i < num_matches; ++i)
        {
            len = (int)STRLEN(matches[i]);
            if (len > 3 && matches[i][len - 3] == '@'
                                  && STRICMP(matches[i] + len - 2, lang) == 0)
                break;
        }
#endif
    if (i >= num_matches || n == FAIL)
    {
#ifdef FEAT_MULTI_LANG
        if (lang != NULL)
            EMSG3(_("E661: Sorry, no '%s' help for %s"), lang, arg);
        else
#endif
            EMSG2(_("E149: Sorry, no help for %s"), arg);
        if (n != FAIL)
            FreeWild(num_matches, matches);
        return;
    }

    /* The first match (in the requested language) is the best match. */
    tag = vim_strsave(matches[i]);
    FreeWild(num_matches, matches);

#ifdef FEAT_GUI
    need_mouse_correct = TRUE;
#endif

    /*
     * Re-use an existing help window or open a new one.
     * Always open a new one for ":tab help".
     */
    if (!curwin->w_buffer->b_help
#ifdef FEAT_WINDOWS
            || cmdmod.tab != 0
#endif
            )
    {
#ifdef FEAT_WINDOWS
        if (cmdmod.tab != 0)
            wp = NULL;
        else
            for (wp = firstwin; wp != NULL; wp = wp->w_next)
                if (wp->w_buffer != NULL && wp->w_buffer->b_help)
                    break;
        if (wp != NULL && wp->w_buffer->b_nwindows > 0)
            win_enter(wp, TRUE);
        else
#endif
        {
            /*
             * There is no help window yet.
             * Try to open the file specified by the "helpfile" option.
             */
            if ((helpfd = mch_fopen((char *)p_hf, READBIN)) == NULL)
            {
                smsg((char_u *)_("Sorry, help file \"%s\" not found"), p_hf);
                goto erret;
            }
            fclose(helpfd);

#ifdef FEAT_WINDOWS
            /* Split off help window; put it at far top if no position
             * specified, the current window is vertically split and
             * narrow. */
            n = WSP_HELP;
# ifdef FEAT_VERTSPLIT
            if (cmdmod.split == 0 && curwin->w_width != Columns
                                                  && curwin->w_width < 80)
                n |= WSP_TOP;
# endif
            if (win_split(0, n) == FAIL)
                goto erret;
#else
            /* use current window */
            if (!can_abandon(curbuf, FALSE))
                goto erret;
#endif

#ifdef FEAT_WINDOWS
            if (curwin->w_height < p_hh)
                win_setheight((int)p_hh);
#endif

            /*
             * Open help file (do_ecmd() will set b_help flag, readfile() will
             * set b_p_ro flag).
             * Set the alternate file to the previously edited file.
             */
            alt_fnum = curbuf->b_fnum;
            (void)do_ecmd(0, NULL, NULL, NULL, ECMD_LASTL,
                                                   ECMD_HIDE + ECMD_SET_HELP);
            if (!cmdmod.keepalt)
                curwin->w_alt_fnum = alt_fnum;
            empty_fnum = curbuf->b_fnum;
        }
    }

    if (!p_im)
        restart_edit = 0;           /* don't want insert mode in help file */

    if (tag != NULL)
        do_tag(tag, DT_HELP, 1, FALSE, TRUE);

    /* Delete the empty buffer if we're not using it.  Careful: autocommands
     * may have jumped to another window, check that the buffer is not in a
     * window. */
    if (empty_fnum != 0 && curbuf->b_fnum != empty_fnum)
    {
        buf = buflist_findnr(empty_fnum);
        if (buf != NULL && buf->b_nwindows == 0)
            wipe_buffer(buf, TRUE);
    }

    /* keep the previous alternate file */
    if (alt_fnum != 0 && curwin->w_alt_fnum == empty_fnum && !cmdmod.keepalt)
        curwin->w_alt_fnum = alt_fnum;

erret:
    vim_free(tag);
}


#if defined(FEAT_MULTI_LANG) || defined(PROTO)
/*
 * In an argument search for a language specifiers in the form "@xx".
 * Changes the "@" to NUL if found, and returns a pointer to "xx".
 * Returns NULL if not found.
 */
    char_u *
check_help_lang(arg)
    char_u *arg;
{
    int len = (int)STRLEN(arg);

    if (len >= 3 && arg[len - 3] == '@' && ASCII_ISALPHA(arg[len - 2])
                                               && ASCII_ISALPHA(arg[len - 1]))
    {
        arg[len - 3] = NUL;             /* remove the '@' */
        return arg + len - 2;
    }
    return NULL;
}
#endif

/*
 * Return a heuristic indicating how well the given string matches.  The
 * smaller the number, the better the match.  This is the order of priorities,
 * from best match to worst match:
 *      - Match with least alpha-numeric characters is better.
 *      - Match with least total characters is better.
 *      - Match towards the start is better.
 *      - Match starting with "+" is worse (feature instead of command)
 * Assumption is made that the matched_string passed has already been found to
 * match some string for which help is requested.  webb.
 */
    int
help_heuristic(matched_string, offset, wrong_case)
    char_u      *matched_string;
    int         offset;                 /* offset for match */
    int         wrong_case;             /* no matching case */
{
    int         num_letters;
    char_u      *p;

    num_letters = 0;
    for (p = matched_string; *p; p++)
        if (ASCII_ISALNUM(*p))
            num_letters++;

    /*
     * Multiply the number of letters by 100 to give it a much bigger
     * weighting than the number of characters.
     * If there only is a match while ignoring case, add 5000.
     * If the match starts in the middle of a word, add 10000 to put it
     * somewhere in the last half.
     * If the match is more than 2 chars from the start, multiply by 200 to
     * put it after matches at the start.
     */
    if (ASCII_ISALNUM(matched_string[offset]) && offset > 0
                                 && ASCII_ISALNUM(matched_string[offset - 1]))
        offset += 10000;
    else if (offset > 2)
        offset *= 200;
    if (wrong_case)
        offset += 5000;
    /* Features are less interesting than the subjects themselves, but "+"
     * alone is not a feature. */
    if (matched_string[0] == '+' && matched_string[1] != NUL)
        offset += 100;
    return (int)(100 * num_letters + STRLEN(matched_string) + offset);
}

/*
 * Compare functions for qsort() below, that checks the help heuristics number
 * that has been put after the tagname by find_tags().
 */
    static int
#ifdef __BORLANDC__
_RTLENTRYF
#endif
help_compare(s1, s2)
    const void  *s1;
    const void  *s2;
{
    char    *p1;
    char    *p2;

    p1 = *(char **)s1 + strlen(*(char **)s1) + 1;
    p2 = *(char **)s2 + strlen(*(char **)s2) + 1;
    return strcmp(p1, p2);
}

/*
 * Find all help tags matching "arg", sort them and return in matches[], with
 * the number of matches in num_matches.
 * The matches will be sorted with a "best" match algorithm.
 * When "keep_lang" is TRUE try keeping the language of the current buffer.
 */
    int
find_help_tags(arg, num_matches, matches, keep_lang)
    char_u      *arg;
    int         *num_matches;
    char_u      ***matches;
    int         keep_lang;
{
    char_u      *s, *d;
    int         i;
    static char *(mtable[]) = {"*", "g*", "[*", "]*", ":*",
                               "/*", "/\\*", "\"*", "**",
                               "/\\(\\)",
                               "?", ":?", "?<CR>", "g?", "g?g?", "g??", "z?",
                               "/\\?", "/\\z(\\)", "\\=", ":s\\=",
                               "[count]", "[quotex]", "[range]",
                               "[pattern]", "\\|", "\\%$"};
    static char *(rtable[]) = {"star", "gstar", "[star", "]star", ":star",
                               "/star", "/\\\\star", "quotestar", "starstar",
                               "/\\\\(\\\\)",
                               "?", ":?", "?<CR>", "g?", "g?g?", "g??", "z?",
                               "/\\\\?", "/\\\\z(\\\\)", "\\\\=", ":s\\\\=",
                               "\\[count]", "\\[quotex]", "\\[range]",
                               "\\[pattern]", "\\\\bar", "/\\\\%\\$"};
    int flags;

    d = IObuff;             /* assume IObuff is long enough! */

    /*
     * Recognize a few exceptions to the rule.  Some strings that contain '*'
     * with "star".  Otherwise '*' is recognized as a wildcard.
     */
    for (i = sizeof(mtable) / sizeof(char *); --i >= 0; )
        if (STRCMP(arg, mtable[i]) == 0)
        {
            STRCPY(d, rtable[i]);
            break;
        }

    if (i < 0)  /* no match in table */
    {
        /* Replace "\S" with "/\\S", etc.  Otherwise every tag is matched.
         * Also replace "\%^" and "\%(", they match every tag too.
         * Also "\zs", "\z1", etc.
         * Also "\@<", "\@=", "\@<=", etc.
         * And also "\_$" and "\_^". */
        if (arg[0] == '\\'
                && ((arg[1] != NUL && arg[2] == NUL)
                    || (vim_strchr((char_u *)"%_z@", arg[1]) != NULL
                                                           && arg[2] != NUL)))
        {
            STRCPY(d, "/\\\\");
            STRCPY(d + 3, arg + 1);
            /* Check for "/\\_$", should be "/\\_\$" */
            if (d[3] == '_' && d[4] == '$')
                STRCPY(d + 4, "\\$");
        }
        else
        {
          /* replace "[:...:]" with "\[:...:]"; "[+...]" with "\[++...]" */
            if (arg[0] == '[' && (arg[1] == ':'
                                         || (arg[1] == '+' && arg[2] == '+')))
              *d++ = '\\';

          for (s = arg; *s; ++s)
          {
            /*
             * Replace "|" with "bar" and '"' with "quote" to match the name of
             * the tags for these commands.
             * Replace "*" with ".*" and "?" with "." to match command line
             * completion.
             * Insert a backslash before '~', '$' and '.' to avoid their
             * special meaning.
             */
            if (d - IObuff > IOSIZE - 10)       /* getting too long!? */
                break;
            switch (*s)
            {
                case '|':   STRCPY(d, "bar");
                            d += 3;
                            continue;
                case '"':   STRCPY(d, "quote");
                            d += 5;
                            continue;
                case '*':   *d++ = '.';
                            break;
                case '?':   *d++ = '.';
                            continue;
                case '$':
                case '.':
                case '~':   *d++ = '\\';
                            break;
            }

            /*
             * Replace "^x" by "CTRL-X". Don't do this for "^_" to make
             * ":help i_^_CTRL-D" work.
             * Insert '-' before and after "CTRL-X" when applicable.
             */
            if (*s < ' ' || (*s == '^' && s[1] && (ASCII_ISALPHA(s[1])
                           || vim_strchr((char_u *)"?@[\\]^", s[1]) != NULL)))
            {
                if (d > IObuff && d[-1] != '_')
                    *d++ = '_';         /* prepend a '_' */
                STRCPY(d, "CTRL-");
                d += 5;
                if (*s < ' ')
                {
#ifdef EBCDIC
                    *d++ = CtrlChar(*s);
#else
                    *d++ = *s + '@';
#endif
                    if (d[-1] == '\\')
                        *d++ = '\\';    /* double a backslash */
                }
                else
                    *d++ = *++s;
                if (s[1] != NUL && s[1] != '_')
                    *d++ = '_';         /* append a '_' */
                continue;
            }
            else if (*s == '^')         /* "^" or "CTRL-^" or "^_" */
                *d++ = '\\';

            /*
             * Insert a backslash before a backslash after a slash, for search
             * pattern tags: "/\|" --> "/\\|".
             */
            else if (s[0] == '\\' && s[1] != '\\'
                                               && *arg == '/' && s == arg + 1)
                *d++ = '\\';

            /* "CTRL-\_" -> "CTRL-\\_" to avoid the special meaning of "\_" in
             * "CTRL-\_CTRL-N" */
            if (STRNICMP(s, "CTRL-\\_", 7) == 0)
            {
                STRCPY(d, "CTRL-\\\\");
                d += 7;
                s += 6;
            }

            *d++ = *s;

            /*
             * If tag starts with ', toss everything after a second '. Fixes
             * CTRL-] on 'option'. (would include the trailing '.').
             */
            if (*s == '\'' && s > arg && *arg == '\'')
                break;
          }
          *d = NUL;
        }
    }

    *matches = (char_u **)"";
    *num_matches = 0;
    flags = TAG_HELP | TAG_REGEXP | TAG_NAMES | TAG_VERBOSE;
    if (keep_lang)
        flags |= TAG_KEEP_LANG;
    if (find_tags(IObuff, num_matches, matches, flags, (int)MAXCOL, NULL) == OK
            && *num_matches > 0)
    {
        /* Sort the matches found on the heuristic number that is after the
         * tag name. */
        qsort((void *)*matches, (size_t)*num_matches,
                                              sizeof(char_u *), help_compare);
        /* Delete more than TAG_MANY to reduce the size of the listing. */
        while (*num_matches > TAG_MANY)
            vim_free((*matches)[--*num_matches]);
    }
    return OK;
}

/*
 * After reading a help file: May cleanup a help buffer when syntax
 * highlighting is not used.
 */
    void
fix_help_buffer()
{
    linenr_T    lnum;
    char_u      *line;
    int         in_example = FALSE;
    int         len;
    char_u      *p;
    char_u      *rt;
    int         mustfree;

    /* set filetype to "help". */
    set_option_value((char_u *)"ft", 0L, (char_u *)"help", OPT_LOCAL);

#ifdef FEAT_SYN_HL
    if (!syntax_present(curbuf))
#endif
    {
        for (lnum = 1; lnum <= curbuf->b_ml.ml_line_count; ++lnum)
        {
            line = ml_get_buf(curbuf, lnum, FALSE);
            len = (int)STRLEN(line);
            if (in_example && len > 0 && !vim_iswhite(line[0]))
            {
                /* End of example: non-white or '<' in first column. */
                if (line[0] == '<')
                {
                    /* blank-out a '<' in the first column */
                    line = ml_get_buf(curbuf, lnum, TRUE);
                    line[0] = ' ';
                }
                in_example = FALSE;
            }
            if (!in_example && len > 0)
            {
                if (line[len - 1] == '>' && (len == 1 || line[len - 2] == ' '))
                {
                    /* blank-out a '>' in the last column (start of example) */
                    line = ml_get_buf(curbuf, lnum, TRUE);
                    line[len - 1] = ' ';
                    in_example = TRUE;
                }
                else if (line[len - 1] == '~')
                {
                    /* blank-out a '~' at the end of line (header marker) */
                    line = ml_get_buf(curbuf, lnum, TRUE);
                    line[len - 1] = ' ';
                }
            }
        }
    }

    /*
     * In the "help.txt" file, add the locally added help files.
     * This uses the very first line in the help file.
     */
    if (fnamecmp(gettail(curbuf->b_fname), "help.txt") == 0)
    {
        for (lnum = 1; lnum < curbuf->b_ml.ml_line_count; ++lnum)
        {
            line = ml_get_buf(curbuf, lnum, FALSE);
            if (strstr((char *)line, "*local-additions*") != NULL)
            {
                /* Go through all directories in 'runtimepath', skipping
                 * $VIMRUNTIME. */
                p = p_rtp;
                while (*p != NUL)
                {
                    copy_option_part(&p, NameBuff, MAXPATHL, ",");
                    mustfree = FALSE;
                    rt = vim_getenv((char_u *)"VIMRUNTIME", &mustfree);
                    if (fullpathcmp(rt, NameBuff, FALSE) != FPC_SAME)
                    {
                        int     fcount;
                        char_u  **fnames;
                        FILE    *fd;
                        char_u  *s;
                        int     fi;
#ifdef FEAT_MBYTE
                        vimconv_T       vc;
                        char_u          *cp;
#endif

                        /* Find all "doc/ *.txt" files in this directory. */
                        add_pathsep(NameBuff);
                        STRCAT(NameBuff, "doc/*.txt");
                        if (gen_expand_wildcards(1, &NameBuff, &fcount,
                                             &fnames, EW_FILE|EW_SILENT) == OK
                                && fcount > 0)
                        {
                            for (fi = 0; fi < fcount; ++fi)
                            {
                                fd = mch_fopen((char *)fnames[fi], "r");
                                if (fd != NULL)
                                {
                                    vim_fgets(IObuff, IOSIZE, fd);
                                    if (IObuff[0] == '*'
                                            && (s = vim_strchr(IObuff + 1, '*'))
                                                                      != NULL)
                                    {
#ifdef FEAT_MBYTE
                                        int     this_utf = MAYBE;
#endif
                                        /* Change tag definition to a
                                         * reference and remove <CR>/<NL>. */
                                        IObuff[0] = '|';
                                        *s = '|';
                                        while (*s != NUL)
                                        {
                                            if (*s == '\r' || *s == '\n')
                                                *s = NUL;
#ifdef FEAT_MBYTE
                                            /* The text is utf-8 when a byte
                                             * above 127 is found and no
                                             * illegal byte sequence is found.
                                             */
                                            if (*s >= 0x80 && this_utf != FALSE)
                                            {
                                                int     l;

                                                this_utf = TRUE;
                                                l = utf_ptr2len(s);
                                                if (l == 1)
                                                    this_utf = FALSE;
                                                s += l - 1;
                                            }
#endif
                                            ++s;
                                        }
#ifdef FEAT_MBYTE
                                        /* The help file is latin1 or utf-8;
                                         * conversion to the current
                                         * 'encoding' may be required. */
                                        vc.vc_type = CONV_NONE;
                                        convert_setup(&vc, (char_u *)(
                                                    this_utf == TRUE ? "utf-8"
                                                          : "latin1"), p_enc);
                                        if (vc.vc_type == CONV_NONE)
                                            /* No conversion needed. */
                                            cp = IObuff;
                                        else
                                        {
                                            /* Do the conversion.  If it fails
                                             * use the unconverted text. */
                                            cp = string_convert(&vc, IObuff,
                                                                        NULL);
                                            if (cp == NULL)
                                                cp = IObuff;
                                        }
                                        convert_setup(&vc, NULL, NULL);

                                        ml_append(lnum, cp, (colnr_T)0, FALSE);
                                        if (cp != IObuff)
                                            vim_free(cp);
#else
                                        ml_append(lnum, IObuff, (colnr_T)0,
                                                                       FALSE);
#endif
                                        ++lnum;
                                    }
                                    fclose(fd);
                                }
                            }
                            FreeWild(fcount, fnames);
                        }
                    }
                    if (mustfree)
                        vim_free(rt);
                }
                break;
            }
        }
    }
}

/*
 * ":exusage"
 */
/*ARGSUSED*/
    void
ex_exusage(eap)
    exarg_T     *eap;
{
    do_cmdline_cmd((char_u *)"help ex-cmd-index");
}

/*
 * ":viusage"
 */
/*ARGSUSED*/
    void
ex_viusage(eap)
    exarg_T     *eap;
{
    do_cmdline_cmd((char_u *)"help normal-index");
}

#if defined(FEAT_EX_EXTRA) || defined(PROTO)
static void helptags_one __ARGS((char_u *dir, char_u *ext, char_u *lang, int add_help_tags));

/*
 * ":helptags"
 */
    void
ex_helptags(eap)
    exarg_T     *eap;
{
    garray_T    ga;
    int         i, j;
    int         len;
#ifdef FEAT_MULTI_LANG
    char_u      lang[2];
#endif
    expand_T    xpc;
    char_u      *dirname;
    char_u      ext[5];
    char_u      fname[8];
    int         filecount;
    char_u      **files;
    int         add_help_tags = FALSE;

    /* Check for ":helptags ++t {dir}". */
    if (STRNCMP(eap->arg, "++t", 3) == 0 && vim_iswhite(eap->arg[3]))
    {
        add_help_tags = TRUE;
        eap->arg = skipwhite(eap->arg + 3);
    }

    ExpandInit(&xpc);
    xpc.xp_context = EXPAND_DIRECTORIES;
    dirname = ExpandOne(&xpc, eap->arg, NULL,
                            WILD_LIST_NOTFOUND|WILD_SILENT, WILD_EXPAND_FREE);
    if (dirname == NULL || !mch_isdir(dirname))
    {
        EMSG2(_("E150: Not a directory: %s"), eap->arg);
        return;
    }

#ifdef FEAT_MULTI_LANG
    /* Get a list of all files in the directory. */
    STRCPY(NameBuff, dirname);
    add_pathsep(NameBuff);
    STRCAT(NameBuff, "*");
    if (gen_expand_wildcards(1, &NameBuff, &filecount, &files,
                                                    EW_FILE|EW_SILENT) == FAIL
            || filecount == 0)
    {
        EMSG2("E151: No match: %s", NameBuff);
        vim_free(dirname);
        return;
    }

    /* Go over all files in the directory to find out what languages are
     * present. */
    ga_init2(&ga, 1, 10);
    for (i = 0; i < filecount; ++i)
    {
        len = (int)STRLEN(files[i]);
        if (len > 4)
        {
            if (STRICMP(files[i] + len - 4, ".txt") == 0)
            {
                /* ".txt" -> language "en" */
                lang[0] = 'e';
                lang[1] = 'n';
            }
            else if (files[i][len - 4] == '.'
                    && ASCII_ISALPHA(files[i][len - 3])
                    && ASCII_ISALPHA(files[i][len - 2])
                    && TOLOWER_ASC(files[i][len - 1]) == 'x')
            {
                /* ".abx" -> language "ab" */
                lang[0] = TOLOWER_ASC(files[i][len - 3]);
                lang[1] = TOLOWER_ASC(files[i][len - 2]);
            }
            else
                continue;

            /* Did we find this language already? */
            for (j = 0; j < ga.ga_len; j += 2)
                if (STRNCMP(lang, ((char_u *)ga.ga_data) + j, 2) == 0)
                    break;
            if (j == ga.ga_len)
            {
                /* New language, add it. */
                if (ga_grow(&ga, 2) == FAIL)
                    break;
                ((char_u *)ga.ga_data)[ga.ga_len++] = lang[0];
                ((char_u *)ga.ga_data)[ga.ga_len++] = lang[1];
            }
        }
    }

    /*
     * Loop over the found languages to generate a tags file for each one.
     */
    for (j = 0; j < ga.ga_len; j += 2)
    {
        STRCPY(fname, "tags-xx");
        fname[5] = ((char_u *)ga.ga_data)[j];
        fname[6] = ((char_u *)ga.ga_data)[j + 1];
        if (fname[5] == 'e' && fname[6] == 'n')
        {
            /* English is an exception: use ".txt" and "tags". */
            fname[4] = NUL;
            STRCPY(ext, ".txt");
        }
        else
        {
            /* Language "ab" uses ".abx" and "tags-ab". */
            STRCPY(ext, ".xxx");
            ext[1] = fname[5];
            ext[2] = fname[6];
        }
        helptags_one(dirname, ext, fname, add_help_tags);
    }

    ga_clear(&ga);
    FreeWild(filecount, files);

#else
    /* No language support, just use "*.txt" and "tags". */
    helptags_one(dirname, (char_u *)".txt", (char_u *)"tags", add_help_tags);
#endif
    vim_free(dirname);
}

    static void
helptags_one(dir, ext, tagfname, add_help_tags)
    char_u      *dir;           /* doc directory */
    char_u      *ext;           /* suffix, ".txt", ".itx", ".frx", etc. */
    char_u      *tagfname;      /* "tags" for English, "tags-fr" for French. */
    int         add_help_tags;  /* add "help-tags" tag */
{
    FILE        *fd_tags;
    FILE        *fd;
    garray_T    ga;
    int         filecount;
    char_u      **files;
    char_u      *p1, *p2;
    int         fi;
    char_u      *s;
    int         i;
    char_u      *fname;
# ifdef FEAT_MBYTE
    int         utf8 = MAYBE;
    int         this_utf8;
    int         firstline;
    int         mix = FALSE;    /* detected mixed encodings */
# endif

    /*
     * Find all *.txt files.
     */
    STRCPY(NameBuff, dir);
    add_pathsep(NameBuff);
    STRCAT(NameBuff, "*");
    STRCAT(NameBuff, ext);
    if (gen_expand_wildcards(1, &NameBuff, &filecount, &files,
                                                    EW_FILE|EW_SILENT) == FAIL
            || filecount == 0)
    {
        if (!got_int)
            EMSG2("E151: No match: %s", NameBuff);
        return;
    }

    /*
     * Open the tags file for writing.
     * Do this before scanning through all the files.
     */
    STRCPY(NameBuff, dir);
    add_pathsep(NameBuff);
    STRCAT(NameBuff, tagfname);
    fd_tags = mch_fopen((char *)NameBuff, "w");
    if (fd_tags == NULL)
    {
        EMSG2(_("E152: Cannot open %s for writing"), NameBuff);
        FreeWild(filecount, files);
        return;
    }

    /*
     * If using the "++t" argument or generating tags for "$VIMRUNTIME/doc"
     * add the "help-tags" tag.
     */
    ga_init2(&ga, (int)sizeof(char_u *), 100);
    if (add_help_tags || fullpathcmp((char_u *)"$VIMRUNTIME/doc",
                                                      dir, FALSE) == FPC_SAME)
    {
        if (ga_grow(&ga, 1) == FAIL)
            got_int = TRUE;
        else
        {
            s = alloc(18 + (unsigned)STRLEN(tagfname));
            if (s == NULL)
                got_int = TRUE;
            else
            {
                sprintf((char *)s, "help-tags\t%s\t1\n", tagfname);
                ((char_u **)ga.ga_data)[ga.ga_len] = s;
                ++ga.ga_len;
            }
        }
    }

    /*
     * Go over all the files and extract the tags.
     */
    for (fi = 0; fi < filecount && !got_int; ++fi)
    {
        fd = mch_fopen((char *)files[fi], "r");
        if (fd == NULL)
        {
            EMSG2(_("E153: Unable to open %s for reading"), files[fi]);
            continue;
        }
        fname = gettail(files[fi]);

# ifdef FEAT_MBYTE
        firstline = TRUE;
# endif
        while (!vim_fgets(IObuff, IOSIZE, fd) && !got_int)
        {
# ifdef FEAT_MBYTE
            if (firstline)
            {
                /* Detect utf-8 file by a non-ASCII char in the first line. */
                this_utf8 = MAYBE;
                for (s = IObuff; *s != NUL; ++s)
                    if (*s >= 0x80)
                    {
                        int l;

                        this_utf8 = TRUE;
                        l = utf_ptr2len(s);
                        if (l == 1)
                        {
                            /* Illegal UTF-8 byte sequence. */
                            this_utf8 = FALSE;
                            break;
                        }
                        s += l - 1;
                    }
                if (this_utf8 == MAYBE)     /* only ASCII characters found */
                    this_utf8 = FALSE;
                if (utf8 == MAYBE)          /* first file */
                    utf8 = this_utf8;
                else if (utf8 != this_utf8)
                {
                    EMSG2(_("E670: Mix of help file encodings within a language: %s"), files[fi]);
                    mix = !got_int;
                    got_int = TRUE;
                }
                firstline = FALSE;
            }
# endif
            p1 = vim_strchr(IObuff, '*');       /* find first '*' */
            while (p1 != NULL)
            {
                p2 = vim_strchr(p1 + 1, '*');   /* find second '*' */
                if (p2 != NULL && p2 > p1 + 1)  /* skip "*" and "**" */
                {
                    for (s = p1 + 1; s < p2; ++s)
                        if (*s == ' ' || *s == '\t' || *s == '|')
                            break;

                    /*
                     * Only accept a *tag* when it consists of valid
                     * characters, there is white space before it and is
                     * followed by a white character or end-of-line.
                     */
                    if (s == p2
                            && (p1 == IObuff || p1[-1] == ' ' || p1[-1] == '\t')
                            && (vim_strchr((char_u *)" \t\n\r", s[1]) != NULL
                                || s[1] == '\0'))
                    {
                        *p2 = '\0';
                        ++p1;
                        if (ga_grow(&ga, 1) == FAIL)
                        {
                            got_int = TRUE;
                            break;
                        }
                        s = alloc((unsigned)(p2 - p1 + STRLEN(fname) + 2));
                        if (s == NULL)
                        {
                            got_int = TRUE;
                            break;
                        }
                        ((char_u **)ga.ga_data)[ga.ga_len] = s;
                        ++ga.ga_len;
                        sprintf((char *)s, "%s\t%s", p1, fname);

                        /* find next '*' */
                        p2 = vim_strchr(p2 + 1, '*');
                    }
                }
                p1 = p2;
            }
            line_breakcheck();
        }

        fclose(fd);
    }

    FreeWild(filecount, files);

    if (!got_int)
    {
        /*
         * Sort the tags.
         */
        sort_strings((char_u **)ga.ga_data, ga.ga_len);

        /*
         * Check for duplicates.
         */
        for (i = 1; i < ga.ga_len; ++i)
        {
            p1 = ((char_u **)ga.ga_data)[i - 1];
            p2 = ((char_u **)ga.ga_data)[i];
            while (*p1 == *p2)
            {
                if (*p2 == '\t')
                {
                    *p2 = NUL;
                    vim_snprintf((char *)NameBuff, MAXPATHL,
                            _("E154: Duplicate tag \"%s\" in file %s/%s"),
                                     ((char_u **)ga.ga_data)[i], dir, p2 + 1);
                    EMSG(NameBuff);
                    *p2 = '\t';
                    break;
                }
                ++p1;
                ++p2;
            }
        }

# ifdef FEAT_MBYTE
        if (utf8 == TRUE)
            fprintf(fd_tags, "!_TAG_FILE_ENCODING\tutf-8\t//\n");
# endif

        /*
         * Write the tags into the file.
         */
        for (i = 0; i < ga.ga_len; ++i)
        {
            s = ((char_u **)ga.ga_data)[i];
            if (STRNCMP(s, "help-tags\t", 10) == 0)
                /* help-tags entry was added in formatted form */
                fputs((char *)s, fd_tags);
            else
            {
                fprintf(fd_tags, "%s\t/*", s);
                for (p1 = s; *p1 != '\t'; ++p1)
                {
                    /* insert backslash before '\\' and '/' */
                    if (*p1 == '\\' || *p1 == '/')
                        putc('\\', fd_tags);
                    putc(*p1, fd_tags);
                }
                fprintf(fd_tags, "*\n");
            }
        }
    }
#ifdef FEAT_MBYTE
    if (mix)
        got_int = FALSE;    /* continue with other languages */
#endif

    for (i = 0; i < ga.ga_len; ++i)
        vim_free(((char_u **)ga.ga_data)[i]);
    ga_clear(&ga);
    fclose(fd_tags);        /* there is no check for an error... */
}
#endif

#if defined(FEAT_SIGNS) || defined(PROTO)

/*
 * Struct to hold the sign properties.
 */
typedef struct sign sign_T;

struct sign
{
    sign_T      *sn_next;       /* next sign in list */
    int         sn_typenr;      /* type number of sign (negative if not equal
                                   to name) */
    char_u      *sn_name;       /* name of sign */
    char_u      *sn_icon;       /* name of pixmap */
#ifdef FEAT_SIGN_ICONS
    void        *sn_image;      /* icon image */
#endif
    char_u      *sn_text;       /* text used instead of pixmap */
    int         sn_line_hl;     /* highlight ID for line */
    int         sn_text_hl;     /* highlight ID for text */
};

static sign_T   *first_sign = NULL;
static int      last_sign_typenr = MAX_TYPENR;  /* is decremented */

static void sign_list_defined __ARGS((sign_T *sp));

/*
 * ":sign" command
 */
    void
ex_sign(eap)
    exarg_T     *eap;
{
    char_u      *arg = eap->arg;
    char_u      *p;
    int         idx;
    sign_T      *sp;
    sign_T      *sp_prev;
    buf_T       *buf;
    static char *cmds[] = {
                        "define",
#define SIGNCMD_DEFINE  0
                        "undefine",
#define SIGNCMD_UNDEFINE 1
                        "list",
#define SIGNCMD_LIST    2
                        "place",
#define SIGNCMD_PLACE   3
                        "unplace",
#define SIGNCMD_UNPLACE 4
                        "jump",
#define SIGNCMD_JUMP    5
#define SIGNCMD_LAST    6
    };

    /* Parse the subcommand. */
    p = skiptowhite(arg);
    if (*p != NUL)
        *p++ = NUL;
    for (idx = 0; ; ++idx)
    {
        if (idx == SIGNCMD_LAST)
        {
            EMSG2(_("E160: Unknown sign command: %s"), arg);
            return;
        }
        if (STRCMP(arg, cmds[idx]) == 0)
            break;
    }
    arg = skipwhite(p);

    if (idx <= SIGNCMD_LIST)
    {
        /*
         * Define, undefine or list signs.
         */
        if (idx == SIGNCMD_LIST && *arg == NUL)
        {
            /* ":sign list": list all defined signs */
            for (sp = first_sign; sp != NULL; sp = sp->sn_next)
                sign_list_defined(sp);
        }
        else if (*arg == NUL)
            EMSG(_("E156: Missing sign name"));
        else
        {
            p = skiptowhite(arg);
            if (*p != NUL)
                *p++ = NUL;
            sp_prev = NULL;
            for (sp = first_sign; sp != NULL; sp = sp->sn_next)
            {
                if (STRCMP(sp->sn_name, arg) == 0)
                    break;
                sp_prev = sp;
            }
            if (idx == SIGNCMD_DEFINE)
            {
                /* ":sign define {name} ...": define a sign */
                if (sp == NULL)
                {
                    /* Allocate a new sign. */
                    sp = (sign_T *)alloc_clear((unsigned)sizeof(sign_T));
                    if (sp == NULL)
                        return;
                    if (sp_prev == NULL)
                        first_sign = sp;
                    else
                        sp_prev->sn_next = sp;
                    sp->sn_name = vim_strnsave(arg, (int)(p - arg));

                    /* If the name is a number use that for the typenr,
                     * otherwise use a negative number. */
                    if (VIM_ISDIGIT(*arg))
                        sp->sn_typenr = atoi((char *)arg);
                    else
                    {
                        sign_T  *lp;
                        int     start = last_sign_typenr;

                        for (lp = first_sign; lp != NULL; lp = lp->sn_next)
                        {
                            if (lp->sn_typenr == last_sign_typenr)
                            {
                                --last_sign_typenr;
                                if (last_sign_typenr == 0)
                                    last_sign_typenr = MAX_TYPENR;
                                if (last_sign_typenr == start)
                                {
                                    EMSG(_("E612: Too many signs defined"));
                                    return;
                                }
                                lp = first_sign;
                                continue;
                            }
                        }

                        sp->sn_typenr = last_sign_typenr--;
                        if (last_sign_typenr == 0)
                            last_sign_typenr = MAX_TYPENR; /* wrap around */
                    }
                }

                /* set values for a defined sign. */
                for (;;)
                {
                    arg = skipwhite(p);
                    if (*arg == NUL)
                        break;
                    p = skiptowhite_esc(arg);
                    if (STRNCMP(arg, "icon=", 5) == 0)
                    {
                        arg += 5;
                        vim_free(sp->sn_icon);
                        sp->sn_icon = vim_strnsave(arg, (int)(p - arg));
                        backslash_halve(sp->sn_icon);
#ifdef FEAT_SIGN_ICONS
                        if (gui.in_use)
                        {
                            out_flush();
                            if (sp->sn_image != NULL)
                                gui_mch_destroy_sign(sp->sn_image);
                            sp->sn_image = gui_mch_register_sign(sp->sn_icon);
                        }
#endif
                    }
                    else if (STRNCMP(arg, "text=", 5) == 0)
                    {
                        char_u  *s;
                        int     cells;
                        int     len;

                        arg += 5;
#ifdef FEAT_MBYTE
                        /* Count cells and check for non-printable chars */
                        if (has_mbyte)
                        {
                            cells = 0;
                            for (s = arg; s < p; s += (*mb_ptr2len)(s))
                            {
                                if (!vim_isprintc((*mb_ptr2char)(s)))
                                    break;
                                cells += (*mb_ptr2cells)(s);
                            }
                        }
                        else
#endif
                        {
                            for (s = arg; s < p; ++s)
                                if (!vim_isprintc(*s))
                                    break;
                            cells = (int)(s - arg);
                        }
                        /* Currently must be one or two display cells */
                        if (s != p || cells < 1 || cells > 2)
                        {
                            *p = NUL;
                            EMSG2(_("E239: Invalid sign text: %s"), arg);
                            return;
                        }

                        vim_free(sp->sn_text);
                        /* Allocate one byte more if we need to pad up
                         * with a space. */
                        len = (int)(p - arg + ((cells == 1) ? 1 : 0));
                        sp->sn_text = vim_strnsave(arg, len);

                        if (sp->sn_text != NULL && cells == 1)
                            STRCPY(sp->sn_text + len - 1, " ");
                    }
                    else if (STRNCMP(arg, "linehl=", 7) == 0)
                    {
                        arg += 7;
                        sp->sn_line_hl = syn_check_group(arg, (int)(p - arg));
                    }
                    else if (STRNCMP(arg, "texthl=", 7) == 0)
                    {
                        arg += 7;
                        sp->sn_text_hl = syn_check_group(arg, (int)(p - arg));
                    }
                    else
                    {
                        EMSG2(_(e_invarg2), arg);
                        return;
                    }
                }
            }
            else if (sp == NULL)
                EMSG2(_("E155: Unknown sign: %s"), arg);
            else if (idx == SIGNCMD_LIST)
                /* ":sign list {name}" */
                sign_list_defined(sp);
            else
            {
                /* ":sign undefine {name}" */
                vim_free(sp->sn_name);
                vim_free(sp->sn_icon);
#ifdef FEAT_SIGN_ICONS
                if (sp->sn_image != NULL)
                {
                    out_flush();
                    gui_mch_destroy_sign(sp->sn_image);
                }
#endif
                vim_free(sp->sn_text);
                if (sp_prev == NULL)
                    first_sign = sp->sn_next;
                else
                    sp_prev->sn_next = sp->sn_next;
                vim_free(sp);
            }
        }
    }
    else
    {
        int             id = -1;
        linenr_T        lnum = -1;
        char_u          *sign_name = NULL;
        char_u          *arg1;

        if (*arg == NUL)
        {
            if (idx == SIGNCMD_PLACE)
            {
                /* ":sign place": list placed signs in all buffers */
                sign_list_placed(NULL);
            }
            else if (idx == SIGNCMD_UNPLACE)
            {
                /* ":sign unplace": remove placed sign at cursor */
                id = buf_findsign_id(curwin->w_buffer, curwin->w_cursor.lnum);
                if (id > 0)
                {
                    buf_delsign(curwin->w_buffer, id);
                    update_debug_sign(curwin->w_buffer, curwin->w_cursor.lnum);
                }
                else
                    EMSG(_("E159: Missing sign number"));
            }
            else
                EMSG(_(e_argreq));
            return;
        }

        if (idx == SIGNCMD_UNPLACE && arg[0] == '*' && arg[1] == NUL)
        {
            /* ":sign unplace *": remove all placed signs */
            buf_delete_all_signs();
            return;
        }

        /* first arg could be placed sign id */
        arg1 = arg;
        if (VIM_ISDIGIT(*arg))
        {
            id = getdigits(&arg);
            if (!vim_iswhite(*arg) && *arg != NUL)
            {
                id = -1;
                arg = arg1;
            }
            else
            {
                arg = skipwhite(arg);
                if (idx == SIGNCMD_UNPLACE && *arg == NUL)
                {
                    /* ":sign unplace {id}": remove placed sign by number */
                    for (buf = firstbuf; buf != NULL; buf = buf->b_next)
                        if ((lnum = buf_delsign(buf, id)) != 0)
                            update_debug_sign(buf, lnum);
                    return;
                }
            }
        }

        /*
         * Check for line={lnum} name={name} and file={fname} or buffer={nr}.
         * Leave "arg" pointing to {fname}.
         */
        for (;;)
        {
            if (STRNCMP(arg, "line=", 5) == 0)
            {
                arg += 5;
                lnum = atoi((char *)arg);
                arg = skiptowhite(arg);
            }
            else if (STRNCMP(arg, "name=", 5) == 0)
            {
                arg += 5;
                sign_name = arg;
                arg = skiptowhite(arg);
                if (*arg != NUL)
                    *arg++ = NUL;
            }
            else if (STRNCMP(arg, "file=", 5) == 0)
            {
                arg += 5;
                buf = buflist_findname(arg);
                break;
            }
            else if (STRNCMP(arg, "buffer=", 7) == 0)
            {
                arg += 7;
                buf = buflist_findnr((int)getdigits(&arg));
                if (*skipwhite(arg) != NUL)
                    EMSG(_(e_trailing));
                break;
            }
            else
            {
                EMSG(_(e_invarg));
                return;
            }
            arg = skipwhite(arg);
        }

        if (buf == NULL)
        {
            EMSG2(_("E158: Invalid buffer name: %s"), arg);
        }
        else if (id <= 0)
        {
            if (lnum >= 0 || sign_name != NULL)
                EMSG(_(e_invarg));
            else
                /* ":sign place file={fname}": list placed signs in one file */
                sign_list_placed(buf);
        }
        else if (idx == SIGNCMD_JUMP)
        {
            /* ":sign jump {id} file={fname}" */
            if (lnum >= 0 || sign_name != NULL)
                EMSG(_(e_invarg));
            else if ((lnum = buf_findsign(buf, id)) > 0)
            {                           /* goto a sign ... */
                if (buf_jump_open_win(buf) != NULL)
                {                       /* ... in a current window */
                    curwin->w_cursor.lnum = lnum;
                    check_cursor_lnum();
                    beginline(BL_WHITE);
                }
                else
                {                       /* ... not currently in a window */
                    char_u      *cmd;

                    cmd = alloc((unsigned)STRLEN(buf->b_fname) + 25);
                    if (cmd == NULL)
                        return;
                    sprintf((char *)cmd, "e +%ld %s", (long)lnum, buf->b_fname);
                    do_cmdline_cmd(cmd);
                    vim_free(cmd);
                }
#ifdef FEAT_FOLDING
                foldOpenCursor();
#endif
            }
            else
                EMSGN(_("E157: Invalid sign ID: %ld"), id);
        }
        else if (idx == SIGNCMD_UNPLACE)
        {
            /* ":sign unplace {id} file={fname}" */
            if (lnum >= 0 || sign_name != NULL)
                EMSG(_(e_invarg));
            else
            {
                lnum = buf_delsign(buf, id);
                update_debug_sign(buf, lnum);
            }
        }
            /* idx == SIGNCMD_PLACE */
        else if (sign_name != NULL)
        {
            for (sp = first_sign; sp != NULL; sp = sp->sn_next)
                if (STRCMP(sp->sn_name, sign_name) == 0)
                    break;
            if (sp == NULL)
            {
                EMSG2(_("E155: Unknown sign: %s"), sign_name);
                return;
            }
            if (lnum > 0)
                /* ":sign place {id} line={lnum} name={name} file={fname}":
                 * place a sign */
                buf_addsign(buf, id, lnum, sp->sn_typenr);
            else
                /* ":sign place {id} file={fname}": change sign type */
                lnum = buf_change_sign_type(buf, id, sp->sn_typenr);
            update_debug_sign(buf, lnum);
        }
        else
            EMSG(_(e_invarg));
    }
}

#if defined(FEAT_SIGN_ICONS) || defined(PROTO)
/*
 * Allocate the icons.  Called when the GUI has started.  Allows defining
 * signs before it starts.
 */
    void
sign_gui_started()
{
    sign_T      *sp;

    for (sp = first_sign; sp != NULL; sp = sp->sn_next)
        if (sp->sn_icon != NULL)
            sp->sn_image = gui_mch_register_sign(sp->sn_icon);
}
#endif

/*
 * List one sign.
 */
    static void
sign_list_defined(sp)
    sign_T      *sp;
{
    char_u      *p;

    smsg((char_u *)"sign %s", sp->sn_name);
    if (sp->sn_icon != NULL)
    {
        MSG_PUTS(" icon=");
        msg_outtrans(sp->sn_icon);
#ifdef FEAT_SIGN_ICONS
        if (sp->sn_image == NULL)
            MSG_PUTS(_(" (NOT FOUND)"));
#else
        MSG_PUTS(_(" (not supported)"));
#endif
    }
    if (sp->sn_text != NULL)
    {
        MSG_PUTS(" text=");
        msg_outtrans(sp->sn_text);
    }
    if (sp->sn_line_hl > 0)
    {
        MSG_PUTS(" linehl=");
        p = get_highlight_name(NULL, sp->sn_line_hl - 1);
        if (p == NULL)
            MSG_PUTS("NONE");
        else
            msg_puts(p);
    }
    if (sp->sn_text_hl > 0)
    {
        MSG_PUTS(" texthl=");
        p = get_highlight_name(NULL, sp->sn_text_hl - 1);
        if (p == NULL)
            MSG_PUTS("NONE");
        else
            msg_puts(p);
    }
}

/*
 * Get highlighting attribute for sign "typenr".
 * If "line" is TRUE: line highl, if FALSE: text highl.
 */
    int
sign_get_attr(typenr, line)
    int         typenr;
    int         line;
{
    sign_T      *sp;

    for (sp = first_sign; sp != NULL; sp = sp->sn_next)
        if (sp->sn_typenr == typenr)
        {
            if (line)
            {
                if (sp->sn_line_hl > 0)
                    return syn_id2attr(sp->sn_line_hl);
            }
            else
            {
                if (sp->sn_text_hl > 0)
                    return syn_id2attr(sp->sn_text_hl);
            }
            break;
        }
    return 0;
}

/*
 * Get text mark for sign "typenr".
 * Returns NULL if there isn't one.
 */
    char_u *
sign_get_text(typenr)
    int         typenr;
{
    sign_T      *sp;

    for (sp = first_sign; sp != NULL; sp = sp->sn_next)
        if (sp->sn_typenr == typenr)
            return sp->sn_text;
    return NULL;
}

#if defined(FEAT_SIGN_ICONS) || defined(PROTO)
    void *
sign_get_image(typenr)
    int         typenr;         /* the attribute which may have a sign */
{
    sign_T      *sp;

    for (sp = first_sign; sp != NULL; sp = sp->sn_next)
        if (sp->sn_typenr == typenr)
            return sp->sn_image;
    return NULL;
}
#endif

/*
 * Get the name of a sign by its typenr.
 */
    char_u *
sign_typenr2name(typenr)
    int         typenr;
{
    sign_T      *sp;

    for (sp = first_sign; sp != NULL; sp = sp->sn_next)
        if (sp->sn_typenr == typenr)
            return sp->sn_name;
    return (char_u *)_("[Deleted]");
}

#endif

#if defined(FEAT_GUI) || defined(FEAT_CLIENTSERVER) || defined(PROTO)
/*
 * ":drop"
 * Opens the first argument in a window.  When there are two or more arguments
 * the argument list is redefined.
 */
    void
ex_drop(eap)
    exarg_T     *eap;
{
    int         split = FALSE;
    win_T       *wp;
    buf_T       *buf;
# ifdef FEAT_WINDOWS
    tabpage_T   *tp;
# endif

    /*
     * Check if the first argument is already being edited in a window.  If
     * so, jump to that window.
     * We would actually need to check all arguments, but that's complicated
     * and mostly only one file is dropped.
     * This also ignores wildcards, since it is very unlikely the user is
     * editing a file name with a wildcard character.
     */
    set_arglist(eap->arg);

    /*
     * Expanding wildcards may result in an empty argument list.  E.g. when
     * editing "foo.pyc" and ".pyc" is in 'wildignore'.  Assume that we
     * already did an error message for this.
     */
    if (ARGCOUNT == 0)
        return;

# ifdef FEAT_WINDOWS
    if (cmdmod.tab)
    {
        /* ":tab drop file ...": open a tab for each argument that isn't
         * edited in a window yet.  It's like ":tab all" but without closing
         * windows or tabs. */
        ex_all(eap);
    }
    else
# endif
    {
        /* ":drop file ...": Edit the first argument.  Jump to an existing
         * window if possible, edit in current window if the current buffer
         * can be abandoned, otherwise open a new window. */
        buf = buflist_findnr(ARGLIST[0].ae_fnum);

        FOR_ALL_TAB_WINDOWS(tp, wp)
        {
            if (wp->w_buffer == buf)
            {
# ifdef FEAT_WINDOWS
                goto_tabpage_win(tp, wp);
# endif
                curwin->w_arg_idx = 0;
                return;
            }
        }

        /*
         * Check whether the current buffer is changed. If so, we will need
         * to split the current window or data could be lost.
         * Skip the check if the 'hidden' option is set, as in this case the
         * buffer won't be lost.
         */
        if (!P_HID(curbuf))
        {
# ifdef FEAT_WINDOWS
            ++emsg_off;
# endif
            split = check_changed(curbuf, TRUE, FALSE, FALSE, FALSE);
# ifdef FEAT_WINDOWS
            --emsg_off;
# else
            if (split)
                return;
# endif
        }

        /* Fake a ":sfirst" or ":first" command edit the first argument. */
        if (split)
        {
            eap->cmdidx = CMD_sfirst;
            eap->cmd[0] = 's';
        }
        else
            eap->cmdidx = CMD_first;
        ex_rewind(eap);
    }
}
#endif