timer_getoverrun(2) System Calls Manual timer_getoverrun(2) timer_getoverrun - POSIX ( ) LIBRARY Real-time library (librt, -lrt) #include int timer_getoverrun(timer_t timerid); glibc (. feature_test_macros(7)): timer_getoverrun(): _POSIX_C_SOURCE >= 199309L timer_getoverrun() << >> (overrun count) , timerid. (expirations) , . (expiration notifications) (SIGEV_SIGNAL) (SIGEV_THREAD). , . , , ( POSIX.1. , , ). - (delivered) (, ) (accepted) (, sigwaitinfo(2)). . -- , . , , . timer_getoverrun() ; 0, . -1, errno . EINVAL timerid . (SIGEV_SIGNAL), Linux si_overrun siginfo_t ( sigaction(2)). , POSIX.1. POSIX.1 . POSIX.1-2008. Linux 2.6. POSIX.1-2001. POSIX.1 specifies that if the timer overrun count is equal to or greater than an implementation-defined maximum, DELAYTIMER_MAX, then timer_getoverrun() should return DELAYTIMER_MAX. However, before Linux 4.19, if the timer overrun value exceeds the maximum representable integer, the counter cycles, starting once more from low values. Since Linux 4.19, timer_getoverrun() returns DELAYTIMER_MAX (defined as INT_MAX in ) in this case (and the overrun value is reset to 0). timer_create(2). . clock_gettime(2), sigaction(2), signalfd(2), sigwaitinfo(2), timer_create(2), timer_delete(2), timer_settime(2), signal(7), time(7) Azamat Hackimov , Dmitry Bolkhovskikh , Yuri Kozlov ; GNU 3 , . . , , . Linux man-pages 6.06 31 2023 . timer_getoverrun(2)