clock(3) Library Functions Manual clock(3) clock - C (libc, -lc) #include clock_t clock(void); clock() , . -- , , clock_t. , CLOCKS_PER_SEC. , (clock_t) -1. attributes(7). +----------------------------+----------------------------------------------------------+--------------------------+ | | | | +----------------------------+----------------------------------------------------------+--------------------------+ |clock() | | MT-Safe | +----------------------------+----------------------------------------------------------+--------------------------+ XSI requires that CLOCKS_PER_SEC equals 1000000 independent of the actual resolution. , clock(), , wait(2) ( wait). Linux , clock(). , times(2), () . C11, POSIX.1-2008. POSIX.1-2001, C89. glibc 2.17 , clock() times(2). , glibc 2.18, clock_gettime(2) ( CLOCK_PROCESS_CPUTIME_ID). ; clock() . , . 32- , CLOCKS_PER_SEC 1000000, clock() 72 . clock_gettime(2), getrusage(2), times(2) () Azamat Hackimov , Dmitriy S. Seregin , Dmitry Bolkhovskikh , Katrin Kutepova , Yuri Kozlov ; GNU (GNU General Public License - GPL, 3 ) , - . - , , () () () . Linux man-pages 6.18 8 2026 . clock(3)