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[emacs/old-mirror.git] / lib-src / movemail.c
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1 /* movemail foo bar -- move file foo to file bar,
2 locking file foo the way /bin/mail respects.
3 Copyright (C) 1986, 1992, 1993, 1994, 1996 Free Software Foundation, Inc.
5 This file is part of GNU Emacs.
7 GNU Emacs is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
10 any later version.
12 GNU Emacs is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU Emacs; see the file COPYING. If not, write to
19 the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
22 /* Important notice: defining MAIL_USE_FLOCK or MAIL_USE_LOCKF *will
23 cause loss of mail* if you do it on a system that does not normally
24 use flock as its way of interlocking access to inbox files. The
25 setting of MAIL_USE_FLOCK and MAIL_USE_LOCKF *must agree* with the
26 system's own conventions. It is not a choice that is up to you.
28 So, if your system uses lock files rather than flock, then the only way
29 you can get proper operation is to enable movemail to write lockfiles there.
30 This means you must either give that directory access modes
31 that permit everyone to write lockfiles in it, or you must make movemail
32 a setuid or setgid program. */
35 * Modified January, 1986 by Michael R. Gretzinger (Project Athena)
37 * Added POP (Post Office Protocol) service. When compiled -DMAIL_USE_POP
38 * movemail will accept input filename arguments of the form
39 * "po:username". This will cause movemail to open a connection to
40 * a pop server running on $MAILHOST (environment variable). Movemail
41 * must be setuid to root in order to work with POP.
43 * New module: popmail.c
44 * Modified routines:
45 * main - added code within #ifdef MAIL_USE_POP; added setuid (getuid ())
46 * after POP code.
47 * New routines in movemail.c:
48 * get_errmsg - return pointer to system error message
50 * Modified August, 1993 by Jonathan Kamens (OpenVision Technologies)
52 * Move all of the POP code into a separate file, "pop.c".
53 * Use strerror instead of get_errmsg.
57 #define NO_SHORTNAMES /* Tell config not to load remap.h */
58 #include <../src/config.h>
59 #include <sys/types.h>
60 #include <sys/stat.h>
61 #include <sys/file.h>
62 #include <stdio.h>
63 #include <errno.h>
64 #include <../src/syswait.h>
65 #include <getopt.h>
66 #ifdef MAIL_USE_POP
67 #include "pop.h"
68 #endif
70 #ifdef MSDOS
71 #undef access
72 #endif /* MSDOS */
74 #ifndef DIRECTORY_SEP
75 #define DIRECTORY_SEP '/'
76 #endif
77 #ifndef IS_DIRECTORY_SEP
78 #define IS_DIRECTORY_SEP(_c_) ((_c_) == DIRECTORY_SEP)
79 #endif
81 #ifdef WINDOWSNT
82 #undef access
83 #undef unlink
84 #define fork() 0
85 #define sys_wait(var) (*(var) = 0)
86 /* Unfortunately, Samba doesn't seem to properly lock Unix files even
87 though the locking call succeeds (and indeed blocks local access from
88 other NT programs). If you have direct file access using an NFS
89 client or something other than Samba, the locking call might work
90 properly - make sure it does before you enable this! */
91 #define DISABLE_DIRECT_ACCESS
92 #endif /* WINDOWSNT */
94 #ifdef USG
95 #include <fcntl.h>
96 #include <unistd.h>
97 #ifndef F_OK
98 #define F_OK 0
99 #define X_OK 1
100 #define W_OK 2
101 #define R_OK 4
102 #endif
103 #endif /* USG */
105 #ifdef HAVE_UNISTD_H
106 #include <unistd.h>
107 #endif
109 #if defined (XENIX) || defined (WINDOWSNT)
110 #include <sys/locking.h>
111 #endif
113 #ifdef MAIL_USE_LOCKF
114 #define MAIL_USE_SYSTEM_LOCK
115 #endif
117 #ifdef MAIL_USE_FLOCK
118 #define MAIL_USE_SYSTEM_LOCK
119 #endif
121 #ifdef MAIL_USE_MMDF
122 extern int lk_open (), lk_close ();
123 #endif
125 #if !defined (MAIL_USE_SYSTEM_LOCK) && !defined (MAIL_USE_MMDF) && \
126 defined (HAVE_LIBMAIL) && defined (HAVE_MAILLOCK_H)
127 #include <maillock.h>
128 /* We can't use maillock unless we know what directory system mail
129 files appear in. */
130 #ifdef MAILDIR
131 #define MAIL_USE_MAILLOCK
132 static char *mail_spool_name ();
133 #endif
134 #endif
136 /* Cancel substitutions made by config.h for Emacs. */
137 #undef open
138 #undef read
139 #undef write
140 #undef close
142 #ifndef errno
143 extern int errno;
144 #endif
145 char *strerror ();
147 void fatal ();
148 void error ();
149 void pfatal_with_name ();
150 void pfatal_and_delete ();
151 char *concat ();
152 long *xmalloc ();
153 int popmail ();
154 int pop_retr ();
155 int mbx_write ();
156 int mbx_delimit_begin ();
157 int mbx_delimit_end ();
159 /* Nonzero means this is name of a lock file to delete on fatal error. */
160 char *delete_lockname;
163 main (argc, argv)
164 int argc;
165 char **argv;
167 char *inname, *outname;
168 int indesc, outdesc;
169 int nread;
170 WAITTYPE status;
171 int c, preserve_mail = 0;
173 #ifndef MAIL_USE_SYSTEM_LOCK
174 struct stat st;
175 long now;
176 int tem;
177 char *lockname, *p;
178 char *tempname;
179 int desc;
180 #endif /* not MAIL_USE_SYSTEM_LOCK */
182 #ifdef MAIL_USE_MAILLOCK
183 char *spool_name;
184 #endif
186 delete_lockname = 0;
188 while ((c = getopt (argc, argv, "p")) != EOF)
190 switch (c) {
191 case 'p':
192 preserve_mail++;
193 break;
194 default:
195 exit(1);
199 if (
200 #ifdef MAIL_USE_POP
201 (argc - optind < 2) || (argc - optind > 3)
202 #else
203 (argc - optind != 2)
204 #endif
207 fprintf (stderr, "Usage: movemail [-p] inbox destfile%s\n",
208 #ifdef MAIL_USE_POP
209 " [POP-password]"
210 #else
212 #endif
214 exit (1);
217 inname = argv[optind];
218 outname = argv[optind+1];
220 #ifdef MAIL_USE_MMDF
221 mmdf_init (argv[0]);
222 #endif
224 if (*outname == 0)
225 fatal ("Destination file name is empty", 0);
227 /* Check access to output file. */
228 if (access (outname, F_OK) == 0 && access (outname, W_OK) != 0)
229 pfatal_with_name (outname);
231 /* Also check that outname's directory is writable to the real uid. */
233 char *buf = (char *) xmalloc (strlen (outname) + 1);
234 char *p;
235 strcpy (buf, outname);
236 p = buf + strlen (buf);
237 while (p > buf && !IS_DIRECTORY_SEP (p[-1]))
238 *--p = 0;
239 if (p == buf)
240 *p++ = '.';
241 if (access (buf, W_OK) != 0)
242 pfatal_with_name (buf);
243 free (buf);
246 #ifdef MAIL_USE_POP
247 if (!strncmp (inname, "po:", 3))
249 int status;
251 status = popmail (inname + 3, outname, preserve_mail,
252 (argc - optind == 3) ? argv[optind+2] : NULL);
253 exit (status);
256 setuid (getuid ());
257 #endif /* MAIL_USE_POP */
259 #ifndef DISABLE_DIRECT_ACCESS
261 /* Check access to input file. */
262 if (access (inname, R_OK | W_OK) != 0)
263 pfatal_with_name (inname);
265 #ifndef MAIL_USE_MMDF
266 #ifndef MAIL_USE_SYSTEM_LOCK
267 #ifdef MAIL_USE_MAILLOCK
268 spool_name = mail_spool_name (inname);
269 if (! spool_name)
270 #endif
272 /* Use a lock file named after our first argument with .lock appended:
273 If it exists, the mail file is locked. */
274 /* Note: this locking mechanism is *required* by the mailer
275 (on systems which use it) to prevent loss of mail.
277 On systems that use a lock file, extracting the mail without locking
278 WILL occasionally cause loss of mail due to timing errors!
280 So, if creation of the lock file fails
281 due to access permission on the mail spool directory,
282 you simply MUST change the permission
283 and/or make movemail a setgid program
284 so it can create lock files properly.
286 You might also wish to verify that your system is one
287 which uses lock files for this purpose. Some systems use other methods.
289 If your system uses the `flock' system call for mail locking,
290 define MAIL_USE_SYSTEM_LOCK in config.h or the s-*.h file
291 and recompile movemail. If the s- file for your system
292 should define MAIL_USE_SYSTEM_LOCK but does not, send a bug report
293 to bug-gnu-emacs@prep.ai.mit.edu so we can fix it. */
295 lockname = concat (inname, ".lock", "");
296 tempname = (char *) xmalloc (strlen (inname) + strlen ("EXXXXXX") + 1);
297 strcpy (tempname, inname);
298 p = tempname + strlen (tempname);
299 while (p != tempname && !IS_DIRECTORY_SEP (p[-1]))
300 p--;
301 *p = 0;
302 strcpy (p, "EXXXXXX");
303 mktemp (tempname);
304 unlink (tempname);
306 while (1)
308 /* Create the lock file, but not under the lock file name. */
309 /* Give up if cannot do that. */
310 desc = open (tempname, O_WRONLY | O_CREAT | O_EXCL, 0666);
311 if (desc < 0)
313 char *message = (char *) xmalloc (strlen (tempname) + 50);
314 sprintf (message, "%s--see source file lib-src/movemail.c",
315 tempname);
316 pfatal_with_name (message);
318 close (desc);
320 tem = link (tempname, lockname);
321 unlink (tempname);
322 if (tem >= 0)
323 break;
324 sleep (1);
326 /* If lock file is five minutes old, unlock it.
327 Five minutes should be good enough to cope with crashes
328 and wedgitude, and long enough to avoid being fooled
329 by time differences between machines. */
330 if (stat (lockname, &st) >= 0)
332 now = time (0);
333 if (st.st_ctime < now - 300)
334 unlink (lockname);
338 delete_lockname = lockname;
340 #endif /* not MAIL_USE_SYSTEM_LOCK */
341 #endif /* not MAIL_USE_MMDF */
343 if (fork () == 0)
345 int lockcount = 0;
346 int status = 0;
347 #if defined (MAIL_USE_MAILLOCK) && defined (HAVE_TOUCHLOCK)
348 long touched_lock, now;
349 #endif
351 setuid (getuid ());
353 #ifndef MAIL_USE_MMDF
354 #ifdef MAIL_USE_SYSTEM_LOCK
355 indesc = open (inname, O_RDWR);
356 #else /* if not MAIL_USE_SYSTEM_LOCK */
357 indesc = open (inname, O_RDONLY);
358 #endif /* not MAIL_USE_SYSTEM_LOCK */
359 #else /* MAIL_USE_MMDF */
360 indesc = lk_open (inname, O_RDONLY, 0, 0, 10);
361 #endif /* MAIL_USE_MMDF */
363 if (indesc < 0)
364 pfatal_with_name (inname);
366 #if defined (BSD_SYSTEM) || defined (XENIX)
367 /* In case movemail is setuid to root, make sure the user can
368 read the output file. */
369 /* This is desirable for all systems
370 but I don't want to assume all have the umask system call */
371 umask (umask (0) & 0333);
372 #endif /* BSD_SYSTEM || XENIX */
373 outdesc = open (outname, O_WRONLY | O_CREAT | O_EXCL, 0666);
374 if (outdesc < 0)
375 pfatal_with_name (outname);
377 /* This label exists so we can retry locking
378 after a delay, if it got EAGAIN or EBUSY. */
379 retry_lock:
381 /* Try to lock it. */
382 #ifdef MAIL_USE_MAILLOCK
383 if (spool_name)
385 /* The "0 - " is to make it a negative number if maillock returns
386 non-zero. */
387 status = 0 - maillock (spool_name, 1);
388 #ifdef HAVE_TOUCHLOCK
389 touched_lock = time (0);
390 #endif
391 lockcount = 5;
393 else
394 #endif /* MAIL_USE_MAILLOCK */
396 #ifdef MAIL_USE_SYSTEM_LOCK
397 #ifdef MAIL_USE_LOCKF
398 status = lockf (indesc, F_LOCK, 0);
399 #else /* not MAIL_USE_LOCKF */
400 #ifdef XENIX
401 status = locking (indesc, LK_RLCK, 0L);
402 #else
403 #ifdef WINDOWSNT
404 status = locking (indesc, LK_RLCK, -1L);
405 #else
406 status = flock (indesc, LOCK_EX);
407 #endif
408 #endif
409 #endif /* not MAIL_USE_LOCKF */
410 #endif /* MAIL_USE_SYSTEM_LOCK */
413 /* If it fails, retry up to 5 times
414 for certain failure codes. */
415 if (status < 0)
417 if (++lockcount <= 5)
419 #ifdef EAGAIN
420 if (errno == EAGAIN)
422 sleep (1);
423 goto retry_lock;
425 #endif
426 #ifdef EBUSY
427 if (errno == EBUSY)
429 sleep (1);
430 goto retry_lock;
432 #endif
435 pfatal_with_name (inname);
439 char buf[1024];
441 while (1)
443 nread = read (indesc, buf, sizeof buf);
444 if (nread != write (outdesc, buf, nread))
446 int saved_errno = errno;
447 unlink (outname);
448 errno = saved_errno;
449 pfatal_with_name (outname);
451 if (nread < sizeof buf)
452 break;
453 #if defined (MAIL_USE_MAILLOCK) && defined (HAVE_TOUCHLOCK)
454 if (spool_name)
456 now = time (0);
457 if (now - touched_lock > 60)
459 touchlock ();
460 touched_lock = now;
463 #endif /* MAIL_USE_MAILLOCK */
467 #ifdef BSD_SYSTEM
468 if (fsync (outdesc) < 0)
469 pfatal_and_delete (outname);
470 #endif
472 /* Check to make sure no errors before we zap the inbox. */
473 if (close (outdesc) != 0)
474 pfatal_and_delete (outname);
476 #ifdef MAIL_USE_SYSTEM_LOCK
477 if (! preserve_mail)
479 #if defined (STRIDE) || defined (XENIX) || defined (WINDOWSNT)
480 /* Stride, xenix have file locking, but no ftruncate.
481 This mess will do. */
482 close (open (inname, O_CREAT | O_TRUNC | O_RDWR, 0666));
483 #else
484 ftruncate (indesc, 0L);
486 #endif /* STRIDE or XENIX */
487 #endif /* MAIL_USE_SYSTEM_LOCK */
489 #ifdef MAIL_USE_MMDF
490 lk_close (indesc, 0, 0, 0);
491 #else
492 close (indesc);
493 #endif
495 #ifndef MAIL_USE_SYSTEM_LOCK
496 if (! preserve_mail)
498 /* Delete the input file; if we can't, at least get rid of its
499 contents. */
500 #ifdef MAIL_UNLINK_SPOOL
501 /* This is generally bad to do, because it destroys the permissions
502 that were set on the file. Better to just empty the file. */
503 if (unlink (inname) < 0 && errno != ENOENT)
504 #endif /* MAIL_UNLINK_SPOOL */
505 creat (inname, 0600);
507 #endif /* not MAIL_USE_SYSTEM_LOCK */
509 #ifdef MAIL_USE_MAILLOCK
510 /* This has to occur in the child, i.e., in the process that
511 acquired the lock! */
512 if (spool_name)
513 mailunlock ();
514 #endif
515 exit (0);
518 wait (&status);
519 if (!WIFEXITED (status))
520 exit (1);
521 else if (WRETCODE (status) != 0)
522 exit (WRETCODE (status));
524 #if !defined (MAIL_USE_MMDF) && !defined (MAIL_USE_SYSTEM_LOCK)
525 #ifdef MAIL_USE_MAILLOCK
526 if (! spool_name)
527 #endif /* MAIL_USE_MAILLOCK */
528 unlink (lockname);
529 #endif /* not MAIL_USE_MMDF and not MAIL_USE_SYSTEM_LOCK */
531 #endif /* ! DISABLE_DIRECT_ACCESS */
533 return 0;
536 #ifdef MAIL_USE_MAILLOCK
537 /* This function uses stat to confirm that the mail directory is
538 identical to the directory of the input file, rather than just
539 string-comparing the two paths, because one or both of them might
540 be symbolic links pointing to some other directory. */
541 static char *
542 mail_spool_name (inname)
543 char *inname;
545 struct stat stat1, stat2;
546 char *indir, *fname;
547 int status;
549 if (! (fname = rindex (inname, '/')))
550 return NULL;
552 fname++;
554 if (stat (MAILDIR, &stat1) < 0)
555 return NULL;
557 indir = (char *) xmalloc (fname - inname + 1);
558 strncpy (indir, inname, fname - inname);
559 indir[fname-inname] = '\0';
562 status = stat (indir, &stat2);
564 free (indir);
566 if (status < 0)
567 return NULL;
569 if ((stat1.st_dev == stat2.st_dev) &&
570 (stat1.st_ino == stat2.st_ino))
571 return fname;
573 return NULL;
575 #endif /* MAIL_USE_MAILLOCK */
577 /* Print error message and exit. */
579 void
580 fatal (s1, s2)
581 char *s1, *s2;
583 if (delete_lockname)
584 unlink (delete_lockname);
585 error (s1, s2);
586 exit (1);
589 /* Print error message. `s1' is printf control string, `s2' is arg for it. */
591 void
592 error (s1, s2, s3)
593 char *s1, *s2, *s3;
595 fprintf (stderr, "movemail: ");
596 fprintf (stderr, s1, s2, s3);
597 fprintf (stderr, "\n");
600 void
601 pfatal_with_name (name)
602 char *name;
604 char *s = concat ("", strerror (errno), " for %s");
605 fatal (s, name);
608 void
609 pfatal_and_delete (name)
610 char *name;
612 char *s = concat ("", strerror (errno), " for %s");
613 unlink (name);
614 fatal (s, name);
617 /* Return a newly-allocated string whose contents concatenate those of s1, s2, s3. */
619 char *
620 concat (s1, s2, s3)
621 char *s1, *s2, *s3;
623 int len1 = strlen (s1), len2 = strlen (s2), len3 = strlen (s3);
624 char *result = (char *) xmalloc (len1 + len2 + len3 + 1);
626 strcpy (result, s1);
627 strcpy (result + len1, s2);
628 strcpy (result + len1 + len2, s3);
629 *(result + len1 + len2 + len3) = 0;
631 return result;
634 /* Like malloc but get fatal error if memory is exhausted. */
636 long *
637 xmalloc (size)
638 unsigned size;
640 long *result = (long *) malloc (size);
641 if (!result)
642 fatal ("virtual memory exhausted", 0);
643 return result;
646 /* This is the guts of the interface to the Post Office Protocol. */
648 #ifdef MAIL_USE_POP
650 #ifndef WINDOWSNT
651 #include <sys/socket.h>
652 #include <netinet/in.h>
653 #include <netdb.h>
654 #else
655 #undef _WINSOCKAPI_
656 #include <winsock.h>
657 #endif
658 #include <pwd.h>
660 #ifdef USG
661 #include <fcntl.h>
662 /* Cancel substitutions made by config.h for Emacs. */
663 #undef open
664 #undef read
665 #undef write
666 #undef close
667 #endif /* USG */
669 #define NOTOK (-1)
670 #define OK 0
671 #define DONE 1
673 char *progname;
674 FILE *sfi;
675 FILE *sfo;
676 char ibuffer[BUFSIZ];
677 char obuffer[BUFSIZ];
678 char Errmsg[80];
680 popmail (user, outfile, preserve, password)
681 char *user;
682 char *outfile;
683 int preserve;
684 char *password;
686 int nmsgs, nbytes;
687 register int i;
688 int mbfi;
689 FILE *mbf;
690 char *getenv ();
691 int mbx_write ();
692 popserver server;
693 extern char *strerror ();
695 server = pop_open (0, user, password, POP_NO_GETPASS);
696 if (! server)
698 error (pop_error);
699 return (1);
702 if (pop_stat (server, &nmsgs, &nbytes))
704 error (pop_error);
705 return (1);
708 if (!nmsgs)
710 pop_close (server);
711 return (0);
714 mbfi = open (outfile, O_WRONLY | O_CREAT | O_EXCL, 0666);
715 if (mbfi < 0)
717 pop_close (server);
718 error ("Error in open: %s, %s", strerror (errno), outfile);
719 return (1);
721 fchown (mbfi, getuid (), -1);
723 if ((mbf = fdopen (mbfi, "wb")) == NULL)
725 pop_close (server);
726 error ("Error in fdopen: %s", strerror (errno));
727 close (mbfi);
728 unlink (outfile);
729 return (1);
732 for (i = 1; i <= nmsgs; i++)
734 mbx_delimit_begin (mbf);
735 if (pop_retr (server, i, mbx_write, mbf) != OK)
737 error (Errmsg);
738 close (mbfi);
739 return (1);
741 mbx_delimit_end (mbf);
742 fflush (mbf);
743 if (ferror (mbf))
745 error ("Error in fflush: %s", strerror (errno));
746 pop_close (server);
747 close (mbfi);
748 return (1);
752 /* On AFS, a call to write only modifies the file in the local
753 * workstation's AFS cache. The changes are not written to the server
754 * until a call to fsync or close is made. Users with AFS home
755 * directories have lost mail when over quota because these checks were
756 * not made in previous versions of movemail. */
758 #ifdef BSD_SYSTEM
759 if (fsync (mbfi) < 0)
761 error ("Error in fsync: %s", strerror (errno));
762 return (1);
764 #endif
766 if (close (mbfi) == -1)
768 error ("Error in close: %s", strerror (errno));
769 return (1);
772 if (! preserve)
773 for (i = 1; i <= nmsgs; i++)
775 if (pop_delete (server, i))
777 error (pop_error);
778 pop_close (server);
779 return (1);
783 if (pop_quit (server))
785 error (pop_error);
786 return (1);
789 return (0);
792 pop_retr (server, msgno, action, arg)
793 popserver server;
794 int (*action) ();
796 extern char *strerror ();
797 char *line;
798 int ret;
800 if (pop_retrieve_first (server, msgno, &line))
802 strncpy (Errmsg, pop_error, sizeof (Errmsg));
803 Errmsg[sizeof (Errmsg)-1] = '\0';
804 return (NOTOK);
807 while (! (ret = pop_retrieve_next (server, &line)))
809 if (! line)
810 break;
812 if ((*action)(line, arg) != OK)
814 strcpy (Errmsg, strerror (errno));
815 pop_close (server);
816 return (NOTOK);
820 if (ret)
822 strncpy (Errmsg, pop_error, sizeof (Errmsg));
823 Errmsg[sizeof (Errmsg)-1] = '\0';
824 return (NOTOK);
827 return (OK);
830 /* Do this as a macro instead of using strcmp to save on execution time. */
831 #define IS_FROM_LINE(a) ((a[0] == 'F') \
832 && (a[1] == 'r') \
833 && (a[2] == 'o') \
834 && (a[3] == 'm') \
835 && (a[4] == ' '))
838 mbx_write (line, mbf)
839 char *line;
840 FILE *mbf;
842 if (IS_FROM_LINE (line))
844 if (fputc ('>', mbf) == EOF)
845 return (NOTOK);
847 if (fputs (line, mbf) == EOF)
848 return (NOTOK);
849 if (fputc (0x0a, mbf) == EOF)
850 return (NOTOK);
851 return (OK);
855 mbx_delimit_begin (mbf)
856 FILE *mbf;
858 if (fputs ("\f\n0, unseen,,\n", mbf) == EOF)
859 return (NOTOK);
860 return (OK);
863 mbx_delimit_end (mbf)
864 FILE *mbf;
866 if (putc ('\037', mbf) == EOF)
867 return (NOTOK);
868 return (OK);
871 #endif /* MAIL_USE_POP */
873 #ifndef HAVE_STRERROR
874 char *
875 strerror (errnum)
876 int errnum;
878 extern char *sys_errlist[];
879 extern int sys_nerr;
881 if (errnum >= 0 && errnum < sys_nerr)
882 return sys_errlist[errnum];
883 return (char *) "Unknown error";
886 #endif /* ! HAVE_STRERROR */