1.\" $NetBSD: posix_spawn_file_actions_addopen.3,v 1.5 2014/02/02 16:59:13 wiz Exp $ 2.\" 3.\" Copyright (c) 2008 Ed Schouten <ed@FreeBSD.org> 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25.\" SUCH DAMAGE. 26.\" 27.\" Portions of this text are reprinted and reproduced in electronic form 28.\" from IEEE Std 1003.1, 2004 Edition, Standard for Information Technology -- 29.\" Portable Operating System Interface (POSIX), The Open Group Base 30.\" Specifications Issue 6, Copyright (C) 2001-2004 by the Institute of 31.\" Electrical and Electronics Engineers, Inc and The Open Group. In the 32.\" event of any discrepancy between this version and the original IEEE and 33.\" The Open Group Standard, the original IEEE and The Open Group Standard is 34.\" the referee document. The original Standard can be obtained online at 35.\" http://www.opengroup.org/unix/online.html. 36.\" 37.\" $FreeBSD: src/lib/libc/gen/posix_spawn_file_actions_addopen.3,v 1.2.2.1.4.1 2010/06/14 02:09:06 kensmith Exp $ 38.\" 39.Dd February 2, 2014 40.Dt POSIX_SPAWN_FILE_ACTIONS_ADDOPEN 3 41.Os 42.Sh NAME 43.Nm posix_spawn_file_actions_addopen , 44.Nm posix_spawn_file_actions_adddup2 , 45.Nm posix_spawn_file_actions_addclose 46.Nd "add open, dup2 or close action to spawn file actions object" 47.Sh LIBRARY 48.Lb libc 49.Sh SYNOPSIS 50.In spawn.h 51.Ft int 52.Fn posix_spawn_file_actions_addopen "posix_spawn_file_actions_t * file_actions" "int fildes" "const char *restrict path" "int oflag" "mode_t mode" 53.Ft int 54.Fn posix_spawn_file_actions_adddup2 "posix_spawn_file_actions_t * file_actions" "int fildes" "int newfildes" 55.Ft int 56.Fn posix_spawn_file_actions_addclose "posix_spawn_file_actions_t * file_actions" "int fildes" 57.Sh DESCRIPTION 58These functions add an open, dup2 or close action to a spawn 59file actions object. 60.Pp 61A spawn file actions object is of type 62.Vt posix_spawn_file_actions_t 63(defined in 64.In spawn.h ) 65and is used to specify a series of actions to be performed by a 66.Fn posix_spawn 67or 68.Fn posix_spawnp 69operation in order to arrive at the set of open file descriptors for the 70child process given the set of open file descriptors of the parent. 71.Pp 72A spawn file actions object, when passed to 73.Fn posix_spawn 74or 75.Fn posix_spawnp , 76specify how the set of open file descriptors in the calling 77process is transformed into a set of potentially open file descriptors 78for the spawned process. 79This transformation is as if the specified sequence of actions was 80performed exactly once, in the context of the spawned process (prior to 81execution of the new process image), in the order in which the actions 82were added to the object; additionally, when the new process image is 83executed, any file descriptor (from this new set) which has its 84.Dv FD_CLOEXEC 85flag set is closed (see 86.Fn posix_spawn ) . 87.Pp 88The 89.Fn posix_spawn_file_actions_addopen 90function adds an open action to the object referenced by 91.Fa file_actions 92that causes the file named by 93.Fa path 94to be opened (as if 95.Bd -literal -offset indent 96open(path, oflag, mode) 97.Ed 98.Pp 99had been called, and the returned file descriptor, if not 100.Fa fildes , 101had been changed to 102.Fa fildes ) 103when a new process is spawned using this file actions object. 104If 105.Fa fildes 106was already an open file descriptor, it is closed before the new 107file is opened. 108.Pp 109The string described by 110.Fa path 111is copied by the 112.Fn posix_spawn_file_actions_addopen 113function. 114.Pp 115The 116.Fn posix_spawn_file_actions_adddup2 117function adds a dup2 action to the object referenced by 118.Fa file_actions 119that causes the file descriptor 120.Fa fildes 121to be duplicated as 122.Fa newfildes 123(as if 124.Bd -literal -offset indent 125dup2(fildes, newfildes) 126.Ed 127.Pp 128had been called) when a new process is spawned using this file actions object. 129.Pp 130The 131.Fn posix_spawn_file_actions_addclose 132function adds a close action to the object referenced by 133.Fa file_actions 134that causes the file descriptor 135.Fa fildes 136to be closed (as if 137.Bd -literal -offset indent 138close(fildes) 139.Ed 140.Pp 141had been called) when a new process is spawned using this file actions 142object. 143.Sh RETURN VALUES 144Upon successful completion, these functions return zero; 145otherwise, an error number is returned to indicate the error. 146.Sh ERRORS 147These 148functions fail if: 149.Bl -tag -width Er 150.It Bq Er EBADF 151The value specified by 152.Fa fildes 153or 154.Fa newfildes 155is negative. 156.It Bq Er EINVAL 157The value specified by 158.Fa file_actions 159is invalid. 160.It Bq Er ENOMEM 161Insufficient memory exists to add to the spawn file actions object. 162.El 163.Sh SEE ALSO 164.Xr close 2 , 165.Xr dup2 2 , 166.Xr open 2 , 167.Xr posix_spawn 3 , 168.Xr posix_spawn_file_actions_destroy 3 , 169.Xr posix_spawn_file_actions_init 3 , 170.Xr posix_spawnp 3 171.Sh STANDARDS 172The 173.Fn posix_spawn_file_actions_addopen , 174.Fn posix_spawn_file_actions_adddup2 175and 176.Fn posix_spawn_file_actions_addclose 177functions conform to 178.St -p1003.1-2001 . 179.Sh HISTORY 180The 181.Fn posix_spawn_file_actions_addopen , 182.Fn posix_spawn_file_actions_adddup2 183and 184.Fn posix_spawn_file_actions_addclose 185functions first appeared in 186.Fx 8.0 187and imported for 188.Nx 6.0 . 189.Sh AUTHORS 190.An Ed Schouten Aq Mt ed@FreeBSD.org 191