nanosleep(2) [freebsd man page]

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

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'').

BSD
								  April 17, 1997							       BSD

nanosleep(3)						     Library Functions Manual						      nanosleep(3)

NAME

       nanosleep - Suspends a process from execution for the specified timer interval (P1003.1b)

LIBRARY

       Realtime Library (librt.so, librt.a)

SYNOPSIS

       #include <time.h>

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

PARAMETERS

       *rqtp   A pointer to the timespec data structure that defines the time interval during which the calling process is suspended.

       *rmtp   A  pointer  to the timespec data structure that receives the amount of time remaining in the previously requested interval, or zero
	       if the full interval has elapsed.

DESCRIPTION

       The nanosleep function suspends a process until one of the following conditions is met:

	  o  The time interval specified in rqtp has elapsed.

	  o  A signal is delivered to the calling process and the action is to deliver a signal to a signal-catching function (or to terminate the
	     process).

       The  suspension	time may be longer than requested because the argument value is rounded up to an integer multiple of the clock resolution,
       or due to the scheduling of other activity. Except when it is interrupted by a signal, the suspension time is not less than the time speci-
       fied by the rqtp argument (as measured by the system clock).

RETURN VALUES

       When the nanosleep function returns because the requested time has elapsed, the call is successful and a value of 0 (zero) is returned.

       If the nanosleep function returns because it was interrupted by a signal, a value of -1 is returned.  If the rmtp argument is not NULL, the
       timespec structure referenced by the call is updated to contain the time remaining in the interval.  If the  rmtp  argument  is	NULL,  the
       remaining time is not returned.

       On an unsuccessful call, a value of -1 is returned and errno is set to indicate that an error occurred.

ERRORS

       The nanosleep function fails under the following conditions:

       [EINTR]	      The nanosleep function was interrupted by a signal.

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

RELATED INFORMATION

       Functions: sleep(1)

       Guide to Realtime Programming delim off

																      nanosleep(3)