1/* Copyright (C) 1991-2022 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, see
16 <https://www.gnu.org/licenses/>. */
17
18#include <sys/times.h>
19#include <time.h>
20
21/* Return the time used by the program so far (user time + system time). */
22clock_t
23clock (void)
24{
25 struct tms buf;
26
27 if (__times (&buf) < 0)
28 return (clock_t) -1;
29
30 return buf.tms_utime + buf.tms_stime;
31}
32

source code of glibc/sysdeps/posix/clock.c