1.\" $OpenBSD: nanosleep.2,v 1.11 2008/10/24 14:34:39 jmc Exp $ 2.\" $NetBSD: nanosleep.2,v 1.1 1997/04/17 18:12:02 jtc Exp $ 3.\" 4.\" Copyright (c) 1986, 1991, 1993 5.\" The Regents of the University of California. All rights reserved. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 3. Neither the name of the University nor the names of its contributors 16.\" may be used to endorse or promote products derived from this software 17.\" without specific prior written permission. 18.\" 19.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29.\" SUCH DAMAGE. 30.\" 31.\" @(#)sleep.3 8.1 (Berkeley) 6/4/93 32.\" 33.Dd $Mdocdate: October 24 2008 $ 34.Dt NANOSLEEP 2 35.Os 36.Sh NAME 37.Nm nanosleep 38.Nd high resolution sleep 39.Sh SYNOPSIS 40.Fd #include <time.h> 41.Ft int 42.Fn nanosleep "const struct timespec *rqtp" "struct timespec *rmtp" 43.Sh DESCRIPTION 44.Fn nanosleep 45suspends execution of the calling process for the time specified. 46An unmasked signal will cause it to terminate the sleep early, 47regardless of the 48.Dv SA_RESTART 49value on the interrupting signal. 50.Sh RETURN VALUES 51If the 52.Fn nanosleep 53function returns because the requested time has elapsed, the value 54returned will be zero. 55.Pp 56If the 57.Fn nanosleep 58function returns due to the delivery of a signal, the value returned 59will be \-1, and the global variable 60.Va errno 61will be set to indicate the interruption. 62If 63.Fa rmtp 64is non-null, the timespec structure it references is updated to contain the 65unslept amount (the request time minus the time actually slept). 66.Sh ERRORS 67If any of the following conditions occur, the 68.Fn nanosleep 69function shall return \-1 and set 70.Va errno 71to the corresponding value. 72.Bl -tag -width Er 73.It Bq Er EFAULT 74Either 75.Fa rqtp 76or 77.Fa rmtp 78points to memory that is not a valid part of the process address space. 79.It Bq Er EINTR 80.Nm 81was interrupted by the delivery of a signal. 82.It Bq Er EINVAL 83.Fa rqtp 84specified a nanosecond value less than zero or greater than 1000 million, 85or a second value less than zero or greater than 100 million. 86.It Bq Er ENOSYS 87.Nm 88is not supported by this implementation. 89.El 90.Sh SEE ALSO 91.Xr sleep 1 , 92.Xr sleep 3 93.Sh STANDARDS 94The 95.Fn nanosleep 96function conforms to 97.St -p1003.1b-93 . 98