POSIX_SPAWN_FILE_ACTIONS_ADDOPEN(3) | Library Functions Manual | POSIX_SPAWN_FILE_ACTIONS_ADDOPEN(3) |
posix_spawn_file_actions_addopen
,
posix_spawn_file_actions_adddup2
,
posix_spawn_file_actions_addclose
—
#include <spawn.h>
int
posix_spawn_file_actions_addopen
(posix_spawn_file_actions_t
* file_actions, int
fildes, const char
*restrict path, int
oflag, mode_t
mode);
int
posix_spawn_file_actions_adddup2
(posix_spawn_file_actions_t
* file_actions, int
fildes, int
newfildes);
int
posix_spawn_file_actions_addclose
(posix_spawn_file_actions_t
* file_actions, int
fildes);
A spawn file actions object is of type
posix_spawn_file_actions_t (defined in
<spawn.h>
) and is used to
specify a series of actions to be performed by a
posix_spawn
() or
posix_spawnp
() operation in order to arrive at the
set of open file descriptors for the child process given the set of open
file descriptors of the parent.
A spawn file actions object, when passed to
posix_spawn
() or
posix_spawnp
(), specify how the set of open file
descriptors in the calling process is transformed into a set of potentially
open file descriptors for the spawned process. This transformation is as if
the specified sequence of actions was performed exactly once, in the context
of the spawned process (prior to execution of the new process image), in the
order in which the actions were added to the object; additionally, when the
new process image is executed, any file descriptor (from this new set) which
has its FD_CLOEXEC
flag set is closed (see
posix_spawn
()).
The posix_spawn_file_actions_addopen
()
function adds an open action to the object referenced by
file_actions that causes the file named by
path to be opened (as if
open(path, oflag, mode)
had been called, and the returned file descriptor, if not fildes, had been changed to fildes) when a new process is spawned using this file actions object. If fildes was already an open file descriptor, it is closed before the new file is opened.
The string described by path is copied by
the posix_spawn_file_actions_addopen
() function.
The posix_spawn_file_actions_adddup2
()
function adds a dup2 action to the object referenced by
file_actions that causes the file descriptor
fildes to be duplicated as
newfildes (as if
dup2(fildes, newfildes)
had been called) when a new process is spawned using this file actions object.
The posix_spawn_file_actions_addclose
()
function adds a close action to the object referenced by
file_actions that causes the file descriptor
fildes to be closed (as if
close(fildes)
had been called) when a new process is spawned using this file actions object.
posix_spawn_file_actions_addopen
(),
posix_spawn_file_actions_adddup2
() and
posix_spawn_file_actions_addclose
() functions conform
to IEEE Std 1003.1-2001 (“POSIX.1”).
posix_spawn_file_actions_addopen
(),
posix_spawn_file_actions_adddup2
() and
posix_spawn_file_actions_addclose
() functions first
appeared in FreeBSD 8.0 and imported for
NetBSD 6.0.
February 2, 2014 | NetBSD 9.2 |