NetBSD/lib/libpthread/pthread_curcpu_np.3

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.\" $NetBSD: pthread_curcpu_np.3,v 1.2 2011/11/10 16:44:47 wiz Exp $
.\"
.\" Copyright (c)2011 YAMAMOTO Takashi,
.\" 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
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.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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
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.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\" ------------------------------------------------------------
.Dd November 10, 2011
.Dt PTHREAD_CURCPU_NP 3
.Os
.\" ------------------------------------------------------------
.Sh NAME
.Nm pthread_curcpu_np
.Nd get current CPU identifier
.\" ------------------------------------------------------------
.Sh SYNOPSIS
.In pthread.h
.\" - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
.Ft unsigned int
.Fn pthread_curcpu_np \
"void"
.\" ------------------------------------------------------------
.Sh DESCRIPTION
The
.Fn pthread_curcpu_np
function provides a way for a thread to know which CPU it's currently running
on.
.Pp
Note that, unless the thread is bound to a specific CPU, the result might be
already stale when the function returns.
However, it still can be useful as a hint to achieve better CPU locality.
.\" ------------------------------------------------------------
.Sh RETURN VALUES
The
.Fn pthread_curcpu_np
function returns the integer identifier of the CPU which is currently
running the calling thread.
.\" ------------------------------------------------------------
.Sh COMPATIBILITY
The
.Fn pthread_curcpu_np
function is a non-standard extension.
.\" ------------------------------------------------------------
.Sh SEE ALSO
.Xr affinity 3 ,
.Xr pthread 3