1 @c Automatically generated from *.c and others (the comments before
2 @c each entry tell you which file and where in that file). DO NOT EDIT!
3 @c Edit the *.c files, configure with --enable-maintainer-mode,
4 @c and let gather-docs build you a new copy.
7 @deftypefn Replacement void* alloca (size_t @var{size})
9 This function allocates memory which will be automatically reclaimed
10 after the procedure exits. The @libib{} implementation does not free
11 the memory immediately but will do so eventually during subsequent
12 calls to this function. Memory is allocated using @code{xmalloc} under
15 The header file @file{alloca-conf.h} can be used in conjunction with the
16 GNU Autoconf test @code{AC_FUNC_ALLOCA} to test for and properly make
17 available this function. The @code{AC_FUNC_ALLOCA} test requires that
18 client code use a block of preprocessor code to be safe (see the Autoconf
19 manual for more); this header incorporates that logic and more, including
20 the possibility of a GCC built-in function.
25 @deftypefn Extension int asprintf (char **@var{resptr}, const char *@var{format}, ...)
27 Like @code{sprintf}, but instead of passing a pointer to a buffer, you
28 pass a pointer to a pointer. This function will compute the size of
29 the buffer needed, allocate memory with @code{malloc}, and store a
30 pointer to the allocated memory in @code{*@var{resptr}}. The value
31 returned is the same as @code{sprintf} would return. If memory could
32 not be allocated, zero is returned and @code{NULL} is stored in
38 @deftypefn Supplemental int atexit (void (*@var{f})())
40 Causes function @var{f} to be called at exit. Returns 0.
45 @deftypefn Supplemental char* basename (const char *@var{name})
47 Returns a pointer to the last component of pathname @var{name}.
48 Behavior is undefined if the pathname ends in a directory separator.
53 @deftypefn Supplemental int bcmp (char *@var{x}, char *@var{y}, int @var{count})
55 Compares the first @var{count} bytes of two areas of memory. Returns
56 zero if they are the same, nonzero otherwise. Returns zero if
57 @var{count} is zero. A nonzero result only indicates a difference,
58 it does not indicate any sorting order (say, by having a positive
59 result mean @var{x} sorts before @var{y}).
64 @deftypefn Supplemental void bcopy (char *@var{in}, char *@var{out}, int @var{length})
66 Copies @var{length} bytes from memory region @var{in} to region
67 @var{out}. The use of @code{bcopy} is deprecated in new programs.
72 @deftypefn Supplemental void* bsearch (const void *@var{key}, const void *@var{base}, size_t @var{nmemb}, size_t @var{size}, int (*@var{compar})(const void *, const void *))
74 Performs a search over an array of @var{nmemb} elements pointed to by
75 @var{base} for a member that matches the object pointed to by @var{key}.
76 The size of each member is specified by @var{size}. The array contents
77 should be sorted in ascending order according to the @var{compar}
78 comparison function. This routine should take two arguments pointing to
79 the @var{key} and to an array member, in that order, and should return an
80 integer less than, equal to, or greater than zero if the @var{key} object
81 is respectively less than, matching, or greater than the array member.
86 @deftypefn Extension char** buildargv (char *@var{sp})
88 Given a pointer to a string, parse the string extracting fields
89 separated by whitespace and optionally enclosed within either single
90 or double quotes (which are stripped off), and build a vector of
91 pointers to copies of the string for each field. The input string
92 remains unchanged. The last element of the vector is followed by a
95 All of the memory for the pointer array and copies of the string
96 is obtained from @code{malloc}. All of the memory can be returned to the
97 system with the single function call @code{freeargv}, which takes the
98 returned result of @code{buildargv}, as it's argument.
100 Returns a pointer to the argument vector if successful. Returns
101 @code{NULL} if @var{sp} is @code{NULL} or if there is insufficient
102 memory to complete building the argument vector.
104 If the input is a null string (as opposed to a @code{NULL} pointer),
105 then buildarg returns an argument vector that has one arg, a null
111 @deftypefn Supplemental void bzero (char *@var{mem}, int @var{count})
113 Zeros @var{count} bytes starting at @var{mem}. Use of this function
114 is deprecated in favor of @code{memset}.
119 @deftypefn Supplemental void* calloc (size_t @var{nelem}, size_t @var{elsize})
121 Uses @code{malloc} to allocate storage for @var{nelem} objects of
122 @var{elsize} bytes each, then zeros the memory.
127 @deftypefn Extension char* choose_temp_base (void)
129 Return a prefix for temporary file names or @code{NULL} if unable to
130 find one. The current directory is chosen if all else fails so the
131 program is exited if a temporary directory can't be found (@code{mktemp}
132 fails). The buffer for the result is obtained with @code{xmalloc}.
134 This function is provided for backwards compatability only. Its use is
139 @c make-temp-file.c:88
140 @deftypefn Replacement char* choose_tmpdir ()
142 Returns a pointer to a directory path suitable for creating temporary
148 @deftypefn Supplemental long clock (void)
150 Returns an approximation of the CPU time used by the process as a
151 @code{clock_t}; divide this number by @samp{CLOCKS_PER_SEC} to get the
152 number of seconds used.
157 @deftypefn Extension char* concat (const char *@var{s1}, const char *@var{s2}, @dots{}, @code{NULL})
159 Concatenate zero or more of strings and return the result in freshly
160 @code{xmalloc}ed memory. Returns @code{NULL} if insufficient memory is
161 available. The argument list is terminated by the first @code{NULL}
162 pointer encountered. Pointers to empty strings are ignored.
167 @deftypefn Extension char** dupargv (char **@var{vector})
169 Duplicate an argument vector. Simply scans through @var{vector},
170 duplicating each argument until the terminating @code{NULL} is found.
171 Returns a pointer to the argument vector if successful. Returns
172 @code{NULL} if there is insufficient memory to complete building the
178 @deftypefn Extension int errno_max (void)
180 Returns the maximum @code{errno} value for which a corresponding
181 symbolic name or message is available. Note that in the case where we
182 use the @code{sys_errlist} supplied by the system, it is possible for
183 there to be more symbolic names than messages, or vice versa. In
184 fact, the manual page for @code{perror(3C)} explicitly warns that one
185 should check the size of the table (@code{sys_nerr}) before indexing
186 it, since new error codes may be added to the system before they are
187 added to the table. Thus @code{sys_nerr} might be smaller than value
188 implied by the largest @code{errno} value defined in @code{<errno.h>}.
190 We return the maximum value that can be used to obtain a meaningful
191 symbolic name or message.
196 @deftypefn Extension int fdmatch (int @var{fd1}, int @var{fd2})
198 Check to see if two open file descriptors refer to the same file.
199 This is useful, for example, when we have an open file descriptor for
200 an unnamed file, and the name of a file that we believe to correspond
201 to that fd. This can happen when we are exec'd with an already open
202 file (@code{stdout} for example) or from the SVR4 @file{/proc} calls
203 that return open file descriptors for mapped address spaces. All we
204 have to do is open the file by name and check the two file descriptors
205 for a match, which is done by comparing major and minor device numbers
211 @deftypefn Supplemental int ffs (int @var{valu})
213 Find the first (least significant) bit set in @var{valu}. Bits are
214 numbered from right to left, starting with bit 1 (corresponding to the
215 value 1). If @var{valu} is zero, zero is returned.
220 @deftypefn Replacement int fnmatch (const char *@var{pattern}, const char *@var{string}, int @var{flags})
222 Matches @var{string} against @var{pattern}, returning zero if it
223 matches, @code{FNM_NOMATCH} if not. @var{pattern} may contain the
224 wildcards @code{?} to match any one character, @code{*} to match any
225 zero or more characters, or a set of alternate characters in square
226 brackets, like @samp{[a-gt8]}, which match one character (@code{a}
227 through @code{g}, or @code{t}, or @code{8}, in this example) if that one
228 character is in the set. A set may be inverted (i.e., match anything
229 except what's in the set) by giving @code{^} or @code{!} as the first
230 character in the set. To include those characters in the set, list them
231 as anything other than the first character of the set. To include a
232 dash in the set, list it last in the set. A backslash character makes
233 the following character not special, so for example you could match
234 against a literal asterisk with @samp{\*}. To match a literal
235 backslash, use @samp{\\}.
237 @code{flags} controls various aspects of the matching process, and is a
238 boolean OR of zero or more of the following values (defined in
245 @var{string} is assumed to be a path name. No wildcard will ever match
249 Do not interpret backslashes as quoting the following special character.
252 A leading period (at the beginning of @var{string}, or if
253 @code{FNM_PATHNAME} after a slash) is not matched by @code{*} or
254 @code{?} but must be matched explicitly.
256 @item FNM_LEADING_DIR
257 Means that @var{string} also matches @var{pattern} if some initial part
258 of @var{string} matches, and is followed by @code{/} and zero or more
259 characters. For example, @samp{foo*} would match either @samp{foobar}
260 or @samp{foobar/grill}.
263 Ignores case when performing the comparison.
270 @deftypefn Extension void freeargv (char **@var{vector})
272 Free an argument vector that was built using @code{buildargv}. Simply
273 scans through @var{vector}, freeing the memory for each argument until
274 the terminating @code{NULL} is found, and then frees @var{vector}
280 @deftypefn Replacement long get_run_time (void)
282 Returns the time used so far, in microseconds. If possible, this is
283 the time used by this process, else it is the elapsed time since the
289 @deftypefn Supplemental char* getcwd (char *@var{pathname}, int @var{len})
291 Copy the absolute pathname for the current working directory into
292 @var{pathname}, which is assumed to point to a buffer of at least
293 @var{len} bytes, and return a pointer to the buffer. If the current
294 directory's path doesn't fit in @var{len} characters, the result is
295 @code{NULL} and @code{errno} is set. If @var{pathname} is a null pointer,
296 @code{getcwd} will obtain @var{len} bytes of space using
302 @deftypefn Supplemental int getpagesize (void)
304 Returns the number of bytes in a page of memory. This is the
305 granularity of many of the system memory management routines. No
306 guarantee is made as to whether or not it is the same as the basic
307 memory management hardware page size.
312 @deftypefn Supplemental char* getpwd (void)
314 Returns the current working directory. This implementation caches the
315 result on the assumption that the process will not call @code{chdir}
316 between calls to @code{getpwd}.
321 @deftypefn Extension void hex_init (void)
323 Initializes the array mapping the current character set to
324 corresponding hex values. This function must be called before any
325 call to @code{hex_p} or @code{hex_value}. If you fail to call it, a
326 default ASCII-based table will normally be used on ASCII systems.
331 @deftypefn Extension int hex_p (int @var{c})
333 Evaluates to non-zero if the given character is a valid hex character,
334 or zero if it is not. Note that the value you pass will be cast to
335 @code{unsigned char} within the macro.
340 @deftypefn Extension int hex_value (int @var{c})
342 Returns the numeric equivalent of the given character when interpreted
343 as a hexidecimal digit. The result is undefined if you pass an
344 invalid hex digit. Note that the value you pass will be cast to
345 @code{unsigned char} within the macro.
350 @deftypefn Supplemental char* index (char *@var{s}, int @var{c})
352 Returns a pointer to the first occurrence of the character @var{c} in
353 the string @var{s}, or @code{NULL} if not found. The use of @code{index} is
354 deprecated in new programs in favor of @code{strchr}.
359 @deftypefn Supplemental void insque (struct qelem *@var{elem}, struct qelem *@var{pred})
360 @deftypefnx Supplemental void remque (struct qelem *@var{elem})
362 Routines to manipulate queues built from doubly linked lists. The
363 @code{insque} routine inserts @var{elem} in the queue immediately
364 after @var{pred}. The @code{remque} routine removes @var{elem} from
365 its containing queue. These routines expect to be passed pointers to
366 structures which have as their first members a forward pointer and a
367 back pointer, like this prototype (although no prototype is provided):
371 struct qelem *q_forw;
372 struct qelem *q_back;
380 @deftypefn Replacement {const char*} lbasename (const char *@var{name})
382 Given a pointer to a string containing a typical pathname
383 (@samp{/usr/src/cmd/ls/ls.c} for example), returns a pointer to the
384 last component of the pathname (@samp{ls.c} in this case). The
385 returned pointer is guaranteed to lie within the original
386 string. This latter fact is not true of many vendor C
387 libraries, which return special strings or modify the passed
388 strings for particular input.
390 In particular, the empty string returns the same empty string,
391 and a path ending in @code{/} returns the empty string after it.
396 @deftypefn Replacement {const char*} lrealpath (const char *@var{name})
398 Given a pointer to a string containing a pathname, returns a canonical
399 version of the filename. Symlinks will be resolved, and ``.'' and ``..''
400 components will be simplified. The returned value will be allocated using
401 @code{malloc}, or @code{NULL} will be returned on a memory allocation error.
405 @c make-relative-prefix.c:24
406 @deftypefn Extension {const char*} make_relative_prefix (const char *@var{progname}, const char *@var{bin_prefix}, const char *@var{prefix})
408 Given three paths @var{progname}, @var{bin_prefix}, @var{prefix},
409 return the path that is in the same position relative to
410 @var{progname}'s directory as @var{prefix} is relative to
411 @var{bin_prefix}. That is, a string starting with the directory
412 portion of @var{progname}, followed by a relative pathname of the
413 difference between @var{bin_prefix} and @var{prefix}.
415 If @var{progname} does not contain any directory separators,
416 @code{make_relative_prefix} will search @env{PATH} to find a program
417 named @var{progname}. Also, if @var{progname} is a symbolic link,
418 the symbolic link will be resolved.
420 For example, if @var{bin_prefix} is @code{/alpha/beta/gamma/gcc/delta},
421 @var{prefix} is @code{/alpha/beta/gamma/omega/}, and @var{progname} is
422 @code{/red/green/blue/gcc}, then this function will return
423 @code{/red/green/blue/../../omega/}.
425 The return value is normally allocated via @code{malloc}. If no
426 relative prefix can be found, return @code{NULL}.
430 @c make-temp-file.c:138
431 @deftypefn Replacement char* make_temp_file (const char *@var{suffix})
433 Return a temporary file name (as a string) or @code{NULL} if unable to
434 create one. @var{suffix} is a suffix to append to the file name. The
435 string is @code{malloc}ed, and the temporary file has been created.
440 @deftypefn Supplemental void* memchr (const void *@var{s}, int @var{c}, size_t @var{n})
442 This function searches memory starting at @code{*@var{s}} for the
443 character @var{c}. The search only ends with the first occurrence of
444 @var{c}, or after @var{length} characters; in particular, a null
445 character does not terminate the search. If the character @var{c} is
446 found within @var{length} characters of @code{*@var{s}}, a pointer
447 to the character is returned. If @var{c} is not found, then @code{NULL} is
453 @deftypefn Supplemental int memcmp (const void *@var{x}, const void *@var{y}, size_t @var{count})
455 Compares the first @var{count} bytes of two areas of memory. Returns
456 zero if they are the same, a value less than zero if @var{x} is
457 lexically less than @var{y}, or a value greater than zero if @var{x}
458 is lexically greater than @var{y}. Note that lexical order is determined
459 as if comparing unsigned char arrays.
464 @deftypefn Supplemental void* memcpy (void *@var{out}, const void *@var{in}, size_t @var{length})
466 Copies @var{length} bytes from memory region @var{in} to region
467 @var{out}. Returns a pointer to @var{out}.
472 @deftypefn Supplemental void* memmove (void *@var{from}, const void *@var{to}, size_t @var{count})
474 Copies @var{count} bytes from memory area @var{from} to memory area
475 @var{to}, returning a pointer to @var{to}.
480 @deftypefn Supplemental void* mempcpy (void *@var{out}, const void *@var{in}, size_t @var{length})
482 Copies @var{length} bytes from memory region @var{in} to region
483 @var{out}. Returns a pointer to @var{out} + @var{length}.
488 @deftypefn Supplemental void* memset (void *@var{s}, int @var{c}, size_t @var{count})
490 Sets the first @var{count} bytes of @var{s} to the constant byte
491 @var{c}, returning a pointer to @var{s}.
496 @deftypefn Replacement int mkstemps (char *@var{template}, int @var{suffix_len})
498 Generate a unique temporary file name from @var{template}.
499 @var{template} has the form:
502 @var{path}/ccXXXXXX@var{suffix}
505 @var{suffix_len} tells us how long @var{suffix} is (it can be zero
506 length). The last six characters of @var{template} before @var{suffix}
507 must be @samp{XXXXXX}; they are replaced with a string that makes the
508 filename unique. Returns a file descriptor open on the file for
514 @deftypefn Extension int pexecute (const char *@var{program}, char * const *@var{argv}, const char *@var{this_pname}, const char *@var{temp_base}, char **@var{errmsg_fmt}, char **@var{errmsg_arg}, int flags)
518 @var{program} and @var{argv} are the arguments to
519 @code{execv}/@code{execvp}.
521 @var{this_pname} is name of the calling program (i.e., @code{argv[0]}).
523 @var{temp_base} is the path name, sans suffix, of a temporary file to
524 use if needed. This is currently only needed for MS-DOS ports that
525 don't use @code{go32} (do any still exist?). Ports that don't need it
526 can pass @code{NULL}.
528 (@code{@var{flags} & PEXECUTE_SEARCH}) is non-zero if @env{PATH}
529 should be searched (??? It's not clear that GCC passes this flag
530 correctly). (@code{@var{flags} & PEXECUTE_FIRST}) is nonzero for the
531 first process in chain. (@code{@var{flags} & PEXECUTE_FIRST}) is
532 nonzero for the last process in chain. The first/last flags could be
533 simplified to only mark the last of a chain of processes but that
534 requires the caller to always mark the last one (and not give up
535 early if some error occurs). It's more robust to require the caller
536 to mark both ends of the chain.
538 The result is the pid on systems like Unix where we
539 @code{fork}/@code{exec} and on systems like WIN32 and OS/2 where we
540 use @code{spawn}. It is up to the caller to wait for the child.
542 The result is the @code{WEXITSTATUS} on systems like MS-DOS where we
543 @code{spawn} and wait for the child here.
545 Upon failure, @var{errmsg_fmt} and @var{errmsg_arg} are set to the
546 text of the error message with an optional argument (if not needed,
547 @var{errmsg_arg} is set to @code{NULL}), and @minus{}1 is returned.
548 @code{errno} is available to the caller to use.
553 @deftypefn Supplemental void psignal (unsigned @var{signo}, char *@var{message})
555 Print @var{message} to the standard error, followed by a colon,
556 followed by the description of the signal specified by @var{signo},
557 followed by a newline.
562 @deftypefn Supplemental int putenv (const char *@var{string})
564 Uses @code{setenv} or @code{unsetenv} to put @var{string} into
565 the environment or remove it. If @var{string} is of the form
566 @samp{name=value} the string is added; if no @samp{=} is present the
567 name is unset/removed.
572 @deftypefn Extension int pwait (int @var{pid}, int *@var{status}, int @var{flags})
574 Waits for a program started by @code{pexecute} to finish.
576 @var{pid} is the process id of the task to wait for. @var{status} is
577 the `status' argument to wait. @var{flags} is currently unused
578 (allows future enhancement without breaking upward compatibility).
581 The result is the pid of the child reaped, or -1 for failure
582 (@code{errno} says why).
584 On systems that don't support waiting for a particular child,
585 @var{pid} is ignored. On systems like MS-DOS that don't really
586 multitask @code{pwait} is just a mechanism to provide a consistent
587 interface for the caller.
592 @deftypefn Supplement {long int} random (void)
593 @deftypefnx Supplement void srandom (unsigned int @var{seed})
594 @deftypefnx Supplement void* initstate (unsigned int @var{seed}, void *@var{arg_state}, unsigned long @var{n})
595 @deftypefnx Supplement void* setstate (void *@var{arg_state})
597 Random number functions. @code{random} returns a random number in the
598 range 0 to @code{LONG_MAX}. @code{srandom} initializes the random
599 number generator to some starting point determined by @var{seed}
600 (else, the values returned by @code{random} are always the same for each
601 run of the program). @code{initstate} and @code{setstate} allow fine-grained
602 control over the state of the random number generator.
607 @deftypefn Extension char* reconcat (char *@var{optr}, const char *@var{s1}, @dots{}, @code{NULL})
609 Same as @code{concat}, except that if @var{optr} is not @code{NULL} it
610 is freed after the string is created. This is intended to be useful
611 when you're extending an existing string or building up a string in a
615 str = reconcat (str, "pre-", str, NULL);
621 @deftypefn Supplemental int rename (const char *@var{old}, const char *@var{new})
623 Renames a file from @var{old} to @var{new}. If @var{new} already
624 exists, it is removed.
629 @deftypefn Supplemental char* rindex (const char *@var{s}, int @var{c})
631 Returns a pointer to the last occurrence of the character @var{c} in
632 the string @var{s}, or @code{NULL} if not found. The use of @code{rindex} is
633 deprecated in new programs in favor of @code{strrchr}.
638 @deftypefn Supplemental int setenv (const char *@var{name}, const char *@var{value}, int @var{overwrite})
639 @deftypefnx Supplemental void unsetenv (const char *@var{name})
641 @code{setenv} adds @var{name} to the environment with value
642 @var{value}. If the name was already present in the environment,
643 the new value will be stored only if @var{overwrite} is nonzero.
644 The companion @code{unsetenv} function removes @var{name} from the
645 environment. This implementation is not safe for multithreaded code.
650 @deftypefn Extension int signo_max (void)
652 Returns the maximum signal value for which a corresponding symbolic
653 name or message is available. Note that in the case where we use the
654 @code{sys_siglist} supplied by the system, it is possible for there to
655 be more symbolic names than messages, or vice versa. In fact, the
656 manual page for @code{psignal(3b)} explicitly warns that one should
657 check the size of the table (@code{NSIG}) before indexing it, since
658 new signal codes may be added to the system before they are added to
659 the table. Thus @code{NSIG} might be smaller than value implied by
660 the largest signo value defined in @code{<signal.h>}.
662 We return the maximum value that can be used to obtain a meaningful
663 symbolic name or message.
668 @deftypefn Supplemental int sigsetmask (int @var{set})
670 Sets the signal mask to the one provided in @var{set} and returns
671 the old mask (which, for libiberty's implementation, will always
672 be the value @code{1}).
677 @deftypefn Supplemental int snprintf (char *@var{buf}, size_t @var{n}, const char *@var{format}, ...)
679 This function is similar to sprintf, but it will print at most @var{n}
680 characters. On error the return value is -1, otherwise it returns the
681 number of characters that would have been printed had @var{n} been
682 sufficiently large, regardless of the actual value of @var{n}. Note
683 some pre-C99 system libraries do not implement this correctly so users
684 cannot generally rely on the return value if the system version of
685 this function is used.
690 @deftypefn Extension char* spaces (int @var{count})
692 Returns a pointer to a memory region filled with the specified
693 number of spaces and null terminated. The returned pointer is
694 valid until at least the next call.
699 @deftypefn Supplemental char* stpcpy (char *@var{dst}, const char *@var{src})
701 Copies the string @var{src} into @var{dst}. Returns a pointer to
702 @var{dst} + strlen(@var{src}).
707 @deftypefn Supplemental char* stpncpy (char *@var{dst}, const char *@var{src}, size_t @var{len})
709 Copies the string @var{src} into @var{dst}, copying exactly @var{len}
710 and padding with zeros if necessary. If @var{len} < strlen(@var{src})
711 then return @var{dst} + @var{len}, otherwise returns @var{dst} +
717 @deftypefn Supplemental int strcasecmp (const char *@var{s1}, const char *@var{s2})
719 A case-insensitive @code{strcmp}.
724 @deftypefn Supplemental char* strchr (const char *@var{s}, int @var{c})
726 Returns a pointer to the first occurrence of the character @var{c} in
727 the string @var{s}, or @code{NULL} if not found. If @var{c} is itself the
728 null character, the results are undefined.
733 @deftypefn Supplemental char* strdup (const char *@var{s})
735 Returns a pointer to a copy of @var{s} in memory obtained from
736 @code{malloc}, or @code{NULL} if insufficient memory was available.
741 @deftypefn Replacement {const char*} strerrno (int @var{errnum})
743 Given an error number returned from a system call (typically returned
744 in @code{errno}), returns a pointer to a string containing the
745 symbolic name of that error number, as found in @code{<errno.h>}.
747 If the supplied error number is within the valid range of indices for
748 symbolic names, but no name is available for the particular error
749 number, then returns the string @samp{Error @var{num}}, where @var{num}
752 If the supplied error number is not within the range of valid
753 indices, then returns @code{NULL}.
755 The contents of the location pointed to are only guaranteed to be
756 valid until the next call to @code{strerrno}.
761 @deftypefn Supplemental char* strerror (int @var{errnoval})
763 Maps an @code{errno} number to an error message string, the contents
764 of which are implementation defined. On systems which have the
765 external variables @code{sys_nerr} and @code{sys_errlist}, these
766 strings will be the same as the ones used by @code{perror}.
768 If the supplied error number is within the valid range of indices for
769 the @code{sys_errlist}, but no message is available for the particular
770 error number, then returns the string @samp{Error @var{num}}, where
771 @var{num} is the error number.
773 If the supplied error number is not a valid index into
774 @code{sys_errlist}, returns @code{NULL}.
776 The returned string is only guaranteed to be valid only until the
777 next call to @code{strerror}.
782 @deftypefn Supplemental int strncasecmp (const char *@var{s1}, const char *@var{s2})
784 A case-insensitive @code{strncmp}.
789 @deftypefn Supplemental int strncmp (const char *@var{s1}, const char *@var{s2}, size_t @var{n})
791 Compares the first @var{n} bytes of two strings, returning a value as
797 @deftypefn Supplemental char* strrchr (const char *@var{s}, int @var{c})
799 Returns a pointer to the last occurrence of the character @var{c} in
800 the string @var{s}, or @code{NULL} if not found. If @var{c} is itself the
801 null character, the results are undefined.
806 @deftypefn Supplemental {const char *} strsignal (int @var{signo})
808 Maps an signal number to an signal message string, the contents of
809 which are implementation defined. On systems which have the external
810 variable @code{sys_siglist}, these strings will be the same as the
811 ones used by @code{psignal()}.
813 If the supplied signal number is within the valid range of indices for
814 the @code{sys_siglist}, but no message is available for the particular
815 signal number, then returns the string @samp{Signal @var{num}}, where
816 @var{num} is the signal number.
818 If the supplied signal number is not a valid index into
819 @code{sys_siglist}, returns @code{NULL}.
821 The returned string is only guaranteed to be valid only until the next
822 call to @code{strsignal}.
827 @deftypefn Extension {const char*} strsigno (int @var{signo})
829 Given an signal number, returns a pointer to a string containing the
830 symbolic name of that signal number, as found in @code{<signal.h>}.
832 If the supplied signal number is within the valid range of indices for
833 symbolic names, but no name is available for the particular signal
834 number, then returns the string @samp{Signal @var{num}}, where
835 @var{num} is the signal number.
837 If the supplied signal number is not within the range of valid
838 indices, then returns @code{NULL}.
840 The contents of the location pointed to are only guaranteed to be
841 valid until the next call to @code{strsigno}.
846 @deftypefn Supplemental char* strstr (const char *@var{string}, const char *@var{sub})
848 This function searches for the substring @var{sub} in the string
849 @var{string}, not including the terminating null characters. A pointer
850 to the first occurrence of @var{sub} is returned, or @code{NULL} if the
851 substring is absent. If @var{sub} points to a string with zero
852 length, the function returns @var{string}.
857 @deftypefn Supplemental double strtod (const char *@var{string}, char **@var{endptr})
859 This ISO C function converts the initial portion of @var{string} to a
860 @code{double}. If @var{endptr} is not @code{NULL}, a pointer to the
861 character after the last character used in the conversion is stored in
862 the location referenced by @var{endptr}. If no conversion is
863 performed, zero is returned and the value of @var{string} is stored in
864 the location referenced by @var{endptr}.
869 @deftypefn Extension int strtoerrno (const char *@var{name})
871 Given the symbolic name of a error number (e.g., @code{EACCES}), map it
872 to an errno value. If no translation is found, returns 0.
877 @deftypefn Supplemental {long int} strtol (const char *@var{string}, char **@var{endptr}, int @var{base})
878 @deftypefnx Supplemental {unsigned long int} strtoul (const char *@var{string}, char **@var{endptr}, int @var{base})
880 The @code{strtol} function converts the string in @var{string} to a
881 long integer value according to the given @var{base}, which must be
882 between 2 and 36 inclusive, or be the special value 0. If @var{base}
883 is 0, @code{strtol} will look for the prefixes @code{0} and @code{0x}
884 to indicate bases 8 and 16, respectively, else default to base 10.
885 When the base is 16 (either explicitly or implicitly), a prefix of
886 @code{0x} is allowed. The handling of @var{endptr} is as that of
887 @code{strtod} above. The @code{strtoul} function is the same, except
888 that the converted value is unsigned.
893 @deftypefn Extension int strtosigno (const char *@var{name})
895 Given the symbolic name of a signal, map it to a signal number. If no
896 translation is found, returns 0.
901 @deftypefn Supplemental char* tmpnam (char *@var{s})
903 This function attempts to create a name for a temporary file, which
904 will be a valid file name yet not exist when @code{tmpnam} checks for
905 it. @var{s} must point to a buffer of at least @code{L_tmpnam} bytes,
906 or be @code{NULL}. Use of this function creates a security risk, and it must
907 not be used in new projects. Use @code{mkstemp} instead.
912 @deftypefn Extension int vasprintf (char **@var{resptr}, const char *@var{format}, va_list @var{args})
914 Like @code{vsprintf}, but instead of passing a pointer to a buffer,
915 you pass a pointer to a pointer. This function will compute the size
916 of the buffer needed, allocate memory with @code{malloc}, and store a
917 pointer to the allocated memory in @code{*@var{resptr}}. The value
918 returned is the same as @code{vsprintf} would return. If memory could
919 not be allocated, zero is returned and @code{NULL} is stored in
920 @code{*@var{resptr}}.
925 @deftypefn Supplemental int vfork (void)
927 Emulates @code{vfork} by calling @code{fork} and returning its value.
932 @deftypefn Supplemental int vprintf (const char *@var{format}, va_list @var{ap})
933 @deftypefnx Supplemental int vfprintf (FILE *@var{stream}, const char *@var{format}, va_list @var{ap})
934 @deftypefnx Supplemental int vsprintf (char *@var{str}, const char *@var{format}, va_list @var{ap})
936 These functions are the same as @code{printf}, @code{fprintf}, and
937 @code{sprintf}, respectively, except that they are called with a
938 @code{va_list} instead of a variable number of arguments. Note that
939 they do not call @code{va_end}; this is the application's
940 responsibility. In @libib{} they are implemented in terms of the
941 nonstandard but common function @code{_doprnt}.
946 @deftypefn Supplemental int vsnprintf (char *@var{buf}, size_t @var{n}, const char *@var{format}, va_list @var{ap})
948 This function is similar to vsprintf, but it will print at most
949 @var{n} characters. On error the return value is -1, otherwise it
950 returns the number of characters that would have been printed had
951 @var{n} been sufficiently large, regardless of the actual value of
952 @var{n}. Note some pre-C99 system libraries do not implement this
953 correctly so users cannot generally rely on the return value if the
954 system version of this function is used.
959 @deftypefn Supplemental int waitpid (int @var{pid}, int *@var{status}, int)
961 This is a wrapper around the @code{wait} function. Any ``special''
962 values of @var{pid} depend on your implementation of @code{wait}, as
963 does the return value. The third argument is unused in @libib{}.
968 @deftypefun int xatexit (void (*@var{fn}) (void))
970 Behaves as the standard @code{atexit} function, but with no limit on
971 the number of registered functions. Returns 0 on success, or @minus{}1 on
972 failure. If you use @code{xatexit} to register functions, you must use
973 @code{xexit} to terminate your program.
978 @deftypefn Replacement void* xcalloc (size_t @var{nelem}, size_t @var{elsize})
980 Allocate memory without fail, and set it to zero. This routine functions
981 like @code{calloc}, but will behave the same as @code{xmalloc} if memory
987 @deftypefn Replacement void xexit (int @var{code})
989 Terminates the program. If any functions have been registered with
990 the @code{xatexit} replacement function, they will be called first.
991 Termination is handled via the system's normal @code{exit} call.
996 @deftypefn Replacement void* xmalloc (size_t)
998 Allocate memory without fail. If @code{malloc} fails, this will print
999 a message to @code{stderr} (using the name set by
1000 @code{xmalloc_set_program_name},
1001 if any) and then call @code{xexit}. Note that it is therefore safe for
1002 a program to contain @code{#define malloc xmalloc} in its source.
1007 @deftypefn Replacement void xmalloc_failed (size_t)
1009 This function is not meant to be called by client code, and is listed
1010 here for completeness only. If any of the allocation routines fail, this
1011 function will be called to print an error message and terminate execution.
1016 @deftypefn Replacement void xmalloc_set_program_name (const char *@var{name})
1018 You can use this to set the name of the program used by
1019 @code{xmalloc_failed} when printing a failure message.
1024 @deftypefn Replacement void* xmemdup (void *@var{input}, size_t @var{copy_size}, size_t @var{alloc_size})
1026 Duplicates a region of memory without fail. First, @var{alloc_size} bytes
1027 are allocated, then @var{copy_size} bytes from @var{input} are copied into
1028 it, and the new memory is returned. If fewer bytes are copied than were
1029 allocated, the remaining memory is zeroed.
1034 @deftypefn Replacement void* xrealloc (void *@var{ptr}, size_t @var{size})
1035 Reallocate memory without fail. This routine functions like @code{realloc},
1036 but will behave the same as @code{xmalloc} if memory cannot be found.
1041 @deftypefn Replacement char* xstrdup (const char *@var{s})
1043 Duplicates a character string without fail, using @code{xmalloc} to
1049 @deftypefn Replacement char* xstrerror (int @var{errnum})
1051 Behaves exactly like the standard @code{strerror} function, but
1052 will never return a @code{NULL} pointer.