view lib/truncate.c @ 40198:5a34193cbc07

long-options: add parse_gnu_standard_options_only Discussed in https://bugs.gnu.org/33468 . * lib/long-options.c (parse_long_options): Use EXIT_SUCCESS instead of 0. (parse_gnu_standard_options_only): Add function to process the GNU default options --help and --version and fail for any other unknown long or short option. See https://gnu.org/prep/standards/html_node/Command_002dLine-Interfaces.html . * lib/long-options.h (parse_gnu_standard_options_only): Declare it. * modules/long-options (depends-on): Add stdbool, exitfail. * top/maint.mk (sc_prohibit_long_options_without_use): Update syntax-check rule, add new function name.
author Bernhard Voelker <mail@bernhard-voelker.de>
date Thu, 29 Nov 2018 09:06:26 +0100
parents b06060465f09
children
line wrap: on
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/* truncate emulations for native Windows.
   Copyright (C) 2017-2019 Free Software Foundation, Inc.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3, or (at your option)
   any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License along
   with this program; if not, see <https://www.gnu.org/licenses/>.  */

#include <config.h>

/* Specification.  */
#include <unistd.h>

#include <errno.h>
#include <fcntl.h>

int
truncate (const char *filename, off_t length)
{
  int fd;

  if (length == 0)
    {
      fd = open (filename, O_WRONLY | O_TRUNC);
      if (fd < 0)
        return -1;
    }
  else
    {
      fd = open (filename, O_WRONLY);
      if (fd < 0)
        return -1;
      if (ftruncate (fd, length) < 0)
        {
          int saved_errno = errno;
          close (fd);
          errno = saved_errno;
          return -1;
        }
    }
  close (fd);
  return 0;
}