1/* Error-checking wrapper for sysconf.
2 Copyright (C) 2017-2023 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#include <errno.h>
20#include <support/check.h>
21#include <support/xunistd.h>
22
23long
24xsysconf (int name)
25{
26 /* Detect errors by a changed errno value, in case -1 is a valid
27 value. Make sure that the caller does not see the zero value for
28 errno. */
29 int old_errno = errno;
30 errno = 0;
31 long result = sysconf (name);
32 if (result == -1 && errno != 0)
33 FAIL_EXIT1 ("sysconf (%d): %m", name);
34 errno = old_errno;
35 return result;
36}
37