1.\" Copyright (c) 2004 Alex Vasylenko <lxv@omut.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.\" Portions of this text are reprinted and reproduced in electronic form 26.\" from IEEE Std 1003.1, 2004 Edition, Standard for Information Technology -- 27.\" Portable Operating System Interface (POSIX), The Open Group Base 28.\" Specifications Issue 6, Copyright (C) 2001-2004 by the Institute of 29.\" Electrical and Electronics Engineers, Inc and The Open Group. In the 30.\" event of any discrepancy between this version and the original IEEE and 31.\" The Open Group Standard, the original IEEE and The Open Group Standard is 32.\" the referee document. The original Standard can be obtained online at 33.\" http://www.opengroup.org/unix/online.html. 34.\" 35.\" $FreeBSD$ 36.\" 37.Dd June 21, 2004 38.Dt PTHREAD_ATFORK 3 39.Os 40.Sh NAME 41.Nm pthread_atfork 42.Nd register fork handlers 43.Sh LIBRARY 44.Lb libpthread 45.Sh SYNOPSIS 46.In pthread.h 47.Ft int 48.Fo pthread_atfork 49.Fa "void \*[lp]*prepare\*[rp]\*[lp]void\*[rp]" 50.Fa "void \*[lp]*parent\*[rp]\*[lp]void\*[rp]" 51.Fa "void \*[lp]*child\*[rp]\*[lp]void\*[rp]" 52.Fc 53.Sh DESCRIPTION 54The 55.Fn pthread_atfork 56function declares fork handlers to be called before and after 57.Xr fork 2 , 58in the context of the thread that called 59.Xr fork 2 . 60.Pp 61The handlers registered with 62.Fn pthread_atfork 63are called at the moments in time described below: 64.Bl -tag -width ".Fa prepare" 65.It Fa prepare 66Before 67.Xr fork 2 68processing commences in the parent process. 69If more than one 70.Fa prepare 71handler is registered they will be called in the opposite order 72they were registered. 73.It Fa parent 74After 75.Xr fork 2 76completes in the parent process. 77If more than one 78.Fa parent 79handler is registered they will be called in the same order 80they were registered. 81.It Fa child 82After 83.Xr fork 2 84processing completes in the child process. 85If more than one 86.Fa child 87handler is registered they will be called in the same order 88they were registered. 89.El 90.Pp 91If no handling is desired at one or more of these three points, 92a null pointer may be passed as the corresponding fork handler. 93.Sh RETURN VALUES 94If successful, the 95.Fn pthread_atfork 96function will return zero. 97Otherwise an error number will be returned to indicate the error. 98.Sh ERRORS 99The 100.Fn pthread_atfork 101function will fail if: 102.Bl -tag -width Er 103.It Bq Er ENOMEM 104Insufficient table space exists to record the fork handler addresses. 105.El 106.Sh SEE ALSO 107.Xr fork 2 , 108.Xr pthread 3 109.Sh STANDARDS 110The 111.Fn pthread_atfork 112function is expected to conform to 113.St -p1003.1 . 114.Sh AUTHORS 115This manpage was written by 116.An Alex Vasylenko 117.Aq lxv@omut.org . 118