clock_nanosleep() causes the current thread to stop executing for the time interval (clocked by clock_id) in rqtp unless: - TIMER_ABSTIME is set in the flags argument - a signal whose action is to invoke a signal catching function is delivered to the current thread - the process is terminated If TIMER_ABSTIME is set in flags, then clock_nanosleep() uses absolute time for the suspension of execution. That is, it stops for: - the absolute time specified by rqtp or until - a signal whose action is to invoke a signal catching function is delivered to the current thread - the process is terminated If TIMER_ABSTIME is set in flags, then if, when clock_nanosleep() is called, rqtp time value less than or equal to specified clock\'s time value, clock_nanosleep() returns immediately and the calling process is *not* suspended. For TIMER_ABSTIME _not_ set: Suspension time is always greater than or equal to the rqtp time interval. [May be greater b/c of rounding or scheduling, just never less than.] Unless clock_nanosleep() is interrupted by a signal. For TIMER_ABSTIME set: Syspension time is always at least until the corresponding clock reaches time rqtp. Unless clock_nanosleep() is interrupted by a signal. clock_nanosleep() does not affect the action/blockage of a signal. clock_nanosleep() fails if clock_id is for the CPU-time clock of the calling thread clock_nanosleep() returns 0 on success (i.e., the full time requested by rqtp has elapsed) For relative clock_nanosleep(), if clock_nanosleep() is interrupted by a signal and rmtp is not-NULL, rmtp contains the amount of time remaining. [If rmtp is NULL, no time is returned.] -- Absolute timers have no effect on rmtp. clock_nanosleep sets errno=EINTR if it was interrupted by a signal clock_nanosleep sets errno=EINVAL if rqpt below 0 or above (or equal to) 1,000 million clock_nanosleep sets errno=EINVAL if TIMER_ABSTIME was specified and rqpt is outside the range for clock_id clock_nanosleep sets errno=EINVAL if clock_id does not refer to a known clock or refers to the CPU-time clock of the calling thread clock_nanosleep sets errno=ENOTSUP if clock_id refers to a clock that clock_nanosleep does not support (ex. if CPU-time clock is not supported) clock_nanosleep() with CLOCK_REALTIME == nanosleep()