.\" $OpenBSD: nanosleep.2,v 1.11 2008/10/24 14:34:39 jmc Exp $ .\" $NetBSD: nanosleep.2,v 1.1 1997/04/17 18:12:02 jtc Exp $ .\" .\" Copyright (c) 1986, 1991, 1993 .\" The Regents of the University of California. All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" 3. Neither the name of the University nor the names of its contributors .\" may be used to endorse or promote products derived from this software .\" without specific prior written permission. .\" .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" .\" @(#)sleep.3 8.1 (Berkeley) 6/4/93 .\" .Dd $Mdocdate: October 24 2008 $ .Dt NANOSLEEP 2 .Os .Sh NAME .Nm nanosleep .Nd high resolution sleep .Sh SYNOPSIS .Fd #include .Ft int .Fn nanosleep "const struct timespec *rqtp" "struct timespec *rmtp" .Sh DESCRIPTION .Fn nanosleep suspends execution of the calling process for the time specified. An unmasked signal will cause it to terminate the sleep early, regardless of the .Dv SA_RESTART value on the interrupting signal. .Sh RETURN VALUES If the .Fn nanosleep function returns because the requested time has elapsed, the value returned will be zero. .Pp If the .Fn nanosleep function returns due to the delivery of a signal, the value returned will be \-1, and the global variable .Va errno will be set to indicate the interruption. If .Fa rmtp is non-null, the timespec structure it references is updated to contain the unslept amount (the request time minus the time actually slept). .Sh ERRORS If any of the following conditions occur, the .Fn nanosleep function shall return \-1 and set .Va errno to the corresponding value. .Bl -tag -width Er .It Bq Er EFAULT Either .Fa rqtp or .Fa rmtp points to memory that is not a valid part of the process address space. .It Bq Er EINTR .Nm was interrupted by the delivery of a signal. .It Bq Er EINVAL .Fa rqtp specified a nanosecond value less than zero or greater than 1000 million, or a second value less than zero or greater than 100 million. .It Bq Er ENOSYS .Nm is not supported by this implementation. .El .Sh SEE ALSO .Xr sleep 1 , .Xr sleep 3 .Sh STANDARDS The .Fn nanosleep function conforms to .St -p1003.1b-93 .