timer_create() creates a timer, timerid, for clock, clockid timerid is unique within the process that called timer_create() until it is deleted timerid is in a "disarmed state" when it is created from timer_create() (i.e., The timer is not active until timer_settime() is called.) evp points to a sigevent structure that defines the notification that will occur when the timer expires If evp == NULL, it is the same as if evp.sigev_notify=SIGEV_SIGNAL and evp.sigev_signo="a default signal number" evp.sigev_value=timerid. clock_id = CLOCK_REALTIME must be supported by timer_create() clock_id = CLOCK_MONOTONIC is supported by timer_create() (with MON support) child processes do not inherit timers during fork() timers are disarmed and deleted by an exec() If _POSIX_CPUTIME is defined, clock_id values = to the CPU-time clock of the process calling timer_create() are allowed If _POSIX_THREAD_CPUTIME is defined, clock_id values = to the CPU-time clock of the thread calling timer_create() are allowed If clock_id = the CPU-time clock of a process or thread that is _not_ the thread calling timer_create(), it is implementation-defined whether timer_create() will attempt to set the timer for that process/thread or just fail. timer_create() returns 0 on success and sets timerid to the correct timer timer_create() returns -1 on failure and timerid is undefined timer_create returns errno = EAGAIN if either: 1) the system does not have enough signal queueing resources to honor the request, or 2) creation of this timer would exceed the allowable timers that the calling process can create timer_create returns errno = EINVAL if clock_id is not a defined clock ID timer_create returns errno = ENOTSUP if the implementation does _not_ support sending a CPU-time clock ID for a different (not the calling) process/thread