clock(3) Library Functions Manual clock(3) clock - (libc -lc) #include clock_t clock(void); clock() . clock_t; CLOCKS_PER_SEC. (clock_t) -1. attributes(7). +------------+------------------------------------+--------------------+ || | | +------------+------------------------------------+--------------------+ |clock() | | MT-Safe | +------------+------------------------------------+--------------------+ XSI CLOCKS_PER_SEC 1000000 . clock() wait(2) ( ). 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). C ; clock() . . 32 CLOCKS_PER_SEC 1000000 72 . clock_gettime(2), getrusage(2), times(2) 3 . . : . 6.18 8 2026 clock(3)