1 /* Return the time used by the program so far (user time + system time). 2 Copyright (C) 1991-2021 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 <sys/times.h> 20 #include <time.h> 21 #include <unistd.h> 22 23 clock_t clock(void)24clock (void) 25 { 26 struct __timespec64 ts; 27 28 _Static_assert (CLOCKS_PER_SEC == 1000000, 29 "CLOCKS_PER_SEC should be 1000000"); 30 31 if (__glibc_unlikely (__clock_gettime64 (CLOCK_PROCESS_CPUTIME_ID, &ts) != 0)) 32 return (clock_t) -1; 33 34 return (ts.tv_sec * CLOCKS_PER_SEC 35 + ts.tv_nsec / (1000000000 / CLOCKS_PER_SEC)); 36 } 37