1.\" Copyright (c) 2003 Alexey Zelkin <phantom@FreeBSD.org> 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.\" $FreeBSD: src/share/man/man3/pthread_switch_add_np.3,v 1.5 2007/10/22 10:08:01 ru Exp $ 26.\" $DragonFly: src/lib/libc_r/man/pthread_switch_add_np.3,v 1.3 2005/08/01 01:49:16 swildner Exp $ 27.\" 28.Dd July 10, 2009 29.Dt PTHREAD_SWITCH_ADD_NP 3 30.Os 31.Sh NAME 32.Nm pthread_switch_add_np , 33.Nm pthread_switch_delete_np 34.Nd thread context switches debugging primitives 35.Sh LIBRARY 36.Lb libpthread 37.Sh SYNOPSIS 38.In pthread.h 39.In pthread_np.h 40.Ft int 41.Fn pthread_switch_add_np "pthread_switch_routine_t routine" 42.Ft int 43.Fn pthread_switch_delete_np "pthread_switch_routine_t routine" 44.Sh DESCRIPTION 45An application is allowed to monitor the thread context switches inside 46the threading library. 47An application can install a routine that gets called every time a thread 48(explicitly created by an application with the 49.Xr pthread_create 3 50function) gets the context switched. 51The routine is passed the thread IDs of the threads that are 52being switched in and out. 53Installation and removal of these hooks may be done using the 54.Fn pthread_switch_add_np 55and 56.Fn pthread_switch_delete_np 57functions respectively. 58.Sh RETURN VALUES 59If successful, 60these functions return 0. 61Otherwise, an error number is returned to indicate the error. 62.Sh ERRORS 63The 64.Fn pthread_switch_add_np 65may fail if: 66.Bl -tag -width Er 67.It Bq Er EINVAL 68.Dv NULL 69pointer was passed in the 70.Fa routine 71argument. 72.El 73.Pp 74The 75.Fn pthread_switch_delete_np 76may fail if: 77.Bl -tag -width Er 78.It Bq Er EINVAL 79The 80.Fa routine 81argument is different from the argument previously passed to the 82.Fn pthread_switch_add_np 83function. 84.El 85.Sh SEE ALSO 86.Xr pthread_create 3 87.Sh AUTHORS 88This manual page was written by 89.An Alexey Zelkin Aq phantom@FreeBSD.org . 90