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NANOSLEEP(2)                BSD System Calls Manual               NANOSLEEP(2)

     nanosleep -- suspend thread execution for an interval measured in

     Standard C Library (libc, -lc)

     #include <time.h>

     nanosleep(const struct timespec *rqtp, struct timespec *rmtp);

     The nanosleep() function causes the calling thread to sleep for the
     amount of time specified in rqtp (the actual time slept may be longer,
     due to system latencies and possible limitations in the timer resolution
     of the hardware).  An unmasked signal will cause nanosleep() to terminate
     the sleep early, regardless of the SA_RESTART value on the interrupting

     If nanosleep() returns because the requested time has elapsed, the value
     returned will be zero.

     If nanosleep() returns due to the delivery of a signal, the value
     returned will be the -1, and the global variable errno will be set to
     indicate the interruption.  If rmtp is non-NULL, the timespec structure
     it references is updated to contain the unslept amount (the request time
     minus the time actually slept).

     The nanosleep() call fails if:

     [EFAULT]           Either rqtp or rmtp points to memory that is not a
                        valid part of the process address space.

     [EINTR]            nanosleep() was interrupted by the delivery of a sig-nal. signal.

     [EINVAL]           rqtp specified a nanosecond value less than zero or
                        greater than or equal to 1000 million.

     [ENOSYS]           nanosleep() is not supported by this implementation.

     sigsuspend(2), sleep(3)

     The nanosleep() function conforms to IEEE Std 1003.1b-1993 (``POSIX.1'').

BSD                             April 17, 1997                             BSD