sysdeps/posix/truncate.c

   1 /* Copyright (C) 1995, 1996 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 Library General Public License as
   6 published by the Free Software Foundation; either version 2 of the
   7 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 Library General Public License for more details.
  13
  14 You should have received a copy of the GNU Library General Public
  15 License along with the GNU C Library; see the file COPYING.LIB.  If
  16 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  17 Cambridge, MA 02139, 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 }