timer_create creates a POSIX.1b interval timer, pointed to by created_timer_id, using the which_clock format. The timer_event_spec points to a sigevent structure if non-NULL. The sigevent structure defines the asynchronous notification that occurs when the timer expires.
The values that clockid_t currently supports for POSIX.1b timers, as defined in include/linux.time.h, are:
- CLOCK_REALTIME
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Systemwide realtime clock.
- CLOCK_MONOTONIC
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Represents monotonic time. Cannot be set.
- CLOCK_PROCESS_CPUTIME_ID
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High resolution per-process timer.
- CLOCK_THREAD_CPUTIME_ID
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Thread-specific timer.
- CLOCK_REALTIME_HR
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High resolution version of CLOCK_REALTIME.
- CLOCK_MONOTONIC_HR
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High resolution version of CLOCK_MONOTONIC.