xref: /netbsd-src/lib/libpthread/pthread_curcpu_np.3 (revision 4a47c092503aad04764e44e6ba833174cd16426e)
1.\"	$NetBSD: pthread_curcpu_np.3,v 1.2 2011/11/10 16:44:47 wiz Exp $
2.\"
3.\" Copyright (c)2011 YAMAMOTO Takashi,
4.\" All rights reserved.
5.\"
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27.\" ------------------------------------------------------------
28.Dd November 10, 2011
29.Dt PTHREAD_CURCPU_NP 3
30.Os
31.\" ------------------------------------------------------------
32.Sh NAME
33.Nm pthread_curcpu_np
34.Nd get current CPU identifier
35.\" ------------------------------------------------------------
36.Sh SYNOPSIS
37.In pthread.h
38.\" - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
39.Ft unsigned int
40.Fn pthread_curcpu_np \
41"void"
42.\" ------------------------------------------------------------
43.Sh DESCRIPTION
44The
45.Fn pthread_curcpu_np
46function provides a way for a thread to know which CPU it's currently running
47on.
48.Pp
49Note that, unless the thread is bound to a specific CPU, the result might be
50already stale when the function returns.
51However, it still can be useful as a hint to achieve better CPU locality.
52.\" ------------------------------------------------------------
53.Sh RETURN VALUES
54The
55.Fn pthread_curcpu_np
56function returns the integer identifier of the CPU which is currently
57running the calling thread.
58.\" ------------------------------------------------------------
59.Sh COMPATIBILITY
60The
61.Fn pthread_curcpu_np
62function is a non-standard extension.
63.\" ------------------------------------------------------------
64.Sh SEE ALSO
65.Xr affinity 3 ,
66.Xr pthread 3
67