/* Error-checking wrapper for sysconf.

   Copyright (C) 2017-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or

   modify it under the terms of the GNU Lesser General Public

   License as published by the Free Software Foundation; either

   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library 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

   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public

   License along with the GNU C Library; if not, see

   <http://www.gnu.org/licenses/>.  */

#include <errno.h>

#include <support/check.h>

#include <support/xunistd.h>

long

xsysconf (int name)

{

  /* Detect errors by a changed errno value, in case -1 is a valid

     value.  Make sure that the caller does not see the zero value for

     errno.  */

  int old_errno = errno;

  errno = 0;

  long result = sysconf (name);

  if (errno != 0)

    FAIL_EXIT1 ("sysconf (%d): %m", name);

  errno = old_errno;

  return result;

}