sysdeps/posix/truncate.c

   1 /* Copyright (C) 1995, 1996, 1997 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, write to the Free
  16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17    02111-1307 USA.  */
  18
  19 #include <sys/types.h>
  20 #include <errno.h>
  21 #include <unistd.h>
  22 #include <fcntl.h>
  23
  24 /* Truncate PATH to LENGTH bytes.  */
  25 int
  26 truncate (path, length)
  27      const char *path;
  28      off_t length;
  29 {
  30   int fd, ret, save;
  31
  32   fd = open (path, O_WRONLY);
  33   if (fd < 0)
  34     return -1;
  35
  36   ret = ftruncate (fd, length);
  37   save = errno;
  38   (void) close (fd);
  39   if (ret < 0)
  40     __set_errno (save);
  41   return ret;
  42 }