2004-12-15 19:37:58 +03:00
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.\" $NetBSD: sched_yield.3,v 1.2 2004/12/15 16:37:58 wiz Exp $
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2004-12-14 04:47:13 +03:00
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.\"
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.\" Copyright (c)2004 YAMAMOTO Takashi,
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.\" All rights reserved.
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.\"
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.\" Redistribution and use in source and binary forms, with or without
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.\" modification, are permitted provided that the following conditions
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.\" are met:
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.\" 1. Redistributions of source code must retain the above copyright
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.\" notice, this list of conditions and the following disclaimer.
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.\" 2. Redistributions in binary form must reproduce the above copyright
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.\" notice, this list of conditions and the following disclaimer in the
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.\" documentation and/or other materials provided with the distribution.
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.\"
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.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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.\" SUCH DAMAGE.
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.\"
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.\" ------------------------------------------------------------
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.Dd December 14, 2004
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.Dt SCHED_YIELD 3
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.Os
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.Sh NAME
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.Nm sched_yield
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.Nd yield a processor
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.\" ------------------------------------------------------------
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.Sh LIBRARY
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.Lb libc
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.\" ------------------------------------------------------------
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.Sh SYNOPSIS
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.In sched.h
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.Ft int
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.Fn sched_yield
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.\" ------------------------------------------------------------
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.Sh DESCRIPTION
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.Fn sched_yield
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yields a processor voluntarily and gives other threads a chance
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2004-12-15 19:37:58 +03:00
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to run without waiting for an involuntary preemptive switch.
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2004-12-14 04:47:13 +03:00
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.\" ------------------------------------------------------------
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.Sh RETURN VALUES
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On success,
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.Fn sched_yield
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returns zero.
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Otherwise, a value of \-1 is returned and
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.Va errno
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is set to indicate the error.
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.\" ------------------------------------------------------------
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.Sh SEE ALSO
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.Xr pthread 3
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.\" ------------------------------------------------------------
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.Sh CAVEATS
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This implementation of
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.Fn sched_yield
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2004-12-15 19:37:58 +03:00
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gives the processor to threads which belong to the same process.
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In other words, it's a no-op in a single threaded application.
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