NAME

     nanosleep — suspend process execution for an interval measured in nanoseconds

LIBRARY

     Standard C Library (libc, -lc)

SYNOPSIS

     #include <time.h>

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

DESCRIPTION

     The nanosleep() system call causes the calling thread to sleep until the time interval
     specified by rqtp has elapsed.  An unmasked signal will cause it to terminate the sleep
     early, regardless of the SA_RESTART value on the interrupting signal.

RETURN VALUES

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

     If the nanosleep() system call returns due to the delivery of a signal, the value returned
     will be -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).

ERRORS

     The nanosleep() system call fails if:

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

     [EINTR]            The nanosleep() system call was interrupted by the delivery of a signal.

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

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

SEE ALSO

     sigsuspend(2), sleep(3)

STANDARDS

     The nanosleep() system call conforms to IEEE Std 1003.1b-1993 (“POSIX.1”).