1.\" Copyright (c) 2008 Ed Schouten <ed@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.\" 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 Mar 24, 2008 38.Dt POSIX_SPAWN_FILE_ACTIONS_ADDOPEN 3 39.Os 40.Sh NAME 41.Nm posix_spawn_file_actions_addopen , 42.Nm posix_spawn_file_actions_adddup2 , 43.Nm posix_spawn_file_actions_addclose 44.Nd "add open, dup2 or close action to spawn file actions object" 45.Sh LIBRARY 46.Lb libc 47.Sh SYNOPSIS 48.In spawn.h 49.Ft int 50.Fn posix_spawn_file_actions_addopen "posix_spawn_file_actions_t * file_actions" "int fildes" "const char *restrict path" "int oflag" "mode_t mode" 51.Ft int 52.Fn posix_spawn_file_actions_adddup2 "posix_spawn_file_actions_t * file_actions" "int fildes" "int newfildes" 53.Ft int 54.Fn posix_spawn_file_actions_addclose "posix_spawn_file_actions_t * file_actions" "int fildes" 55.Sh DESCRIPTION 56These functions add an open, dup2 or close action to a spawn 57file actions object. 58.Pp 59A spawn file actions object is of type 60.Vt posix_spawn_file_actions_t 61(defined in 62.In spawn.h ) 63and is used to specify a series of actions to be performed by a 64.Fn posix_spawn 65or 66.Fn posix_spawnp 67operation in order to arrive at the set of open file descriptors for the 68child process given the set of open file descriptors of the parent. 69.Pp 70A spawn file actions object, when passed to 71.Fn posix_spawn 72or 73.Fn posix_spawnp , 74specify how the set of open file descriptors in the calling 75process is transformed into a set of potentially open file descriptors 76for the spawned process. 77This transformation is as if the specified sequence of actions was 78performed exactly once, in the context of the spawned process (prior to 79execution of the new process image), in the order in which the actions 80were added to the object; additionally, when the new process image is 81executed, any file descriptor (from this new set) which has its 82.Dv FD_CLOEXEC 83flag set is closed (see 84.Fn posix_spawn ) . 85.Pp 86The 87.Fn posix_spawn_file_actions_addopen 88function adds an open action to the object referenced by 89.Fa file_actions 90that causes the file named by 91.Fa path 92to be opened (as if 93.Bd -literal -offset indent 94open(path, oflag, mode) 95.Ed 96.Pp 97had been called, and the returned file descriptor, if not 98.Fa fildes , 99had been changed to 100.Fa fildes ) 101when a new process is spawned using this file actions object. 102If 103.Fa fildes 104was already an open file descriptor, it is closed before the new 105file is opened. 106.Pp 107The string described by 108.Fa path 109is copied by the 110.Fn posix_spawn_file_actions_addopen 111function. 112.Pp 113The 114.Fn posix_spawn_file_actions_adddup2 115function adds a dup2 action to the object referenced by 116.Fa file_actions 117that causes the file descriptor 118.Fa fildes 119to be duplicated as 120.Fa newfildes 121(as if 122.Bd -literal -offset indent 123dup2(fildes, newfildes) 124.Ed 125.Pp 126had been called) when a new process is spawned using this file actions object. 127.Pp 128The 129.Fn posix_spawn_file_actions_addclose 130function adds a close action to the object referenced by 131.Fa file_actions 132that causes the file descriptor 133.Fa fildes 134to be closed (as if 135.Bd -literal -offset indent 136close(fildes) 137.Ed 138.Pp 139had been called) when a new process is spawned using this file actions 140object. 141.Sh RETURN VALUES 142Upon successful completion, these functions return zero; 143otherwise, an error number is returned to indicate the error. 144.Sh ERRORS 145These 146functions fail if: 147.Bl -tag -width Er 148.It Bq Er EINVAL 149The value specified by 150.Fa fildes 151or 152.Fa newfildes 153is negative. 154.It Bq Er ENOMEM 155Insufficient memory exists to add to the spawn file actions object. 156.El 157.Sh SEE ALSO 158.Xr close 2 , 159.Xr dup2 2 , 160.Xr open 2 , 161.Xr posix_spawn 3 , 162.Xr posix_spawn_file_actions_destroy 3 , 163.Xr posix_spawn_file_actions_init 3 , 164.Xr posix_spawnp 3 165.Sh STANDARDS 166The 167.Fn posix_spawn_file_actions_addopen , 168.Fn posix_spawn_file_actions_adddup2 169and 170.Fn posix_spawn_file_actions_addclose 171functions conform to 172.St -p1003.1-2001 . 173.Sh HISTORY 174The 175.Fn posix_spawn_file_actions_addopen , 176.Fn posix_spawn_file_actions_adddup2 177and 178.Fn posix_spawn_file_actions_addclose 179functions first appeared in 180.Fx 8.0 . 181.Sh AUTHORS 182.An Ed Schouten Aq ed@FreeBSD.org 183