NAME

posix_spawnattr_getexecfd_np, posix_spawnattr_setexecfd_np — get and set the spawn-execfd attribute of a spawn attributes object

LIBRARY

Standard C Library (libc, -lc)

SYNOPSIS

#include <spawn.h>

int
posix_spawnattr_getexecfd_np(const posix_spawnattr_t *restrict attr, int *restrict fdp);

int
posix_spawnattr_setexecfd_np(posix_spawnattr_t *attr, int fd);

DESCRIPTION

The posix_spawnattr_getexecfd_np() function obtains the value of the spawn-execfd attribute from the attributes object referenced by attr.

The posix_spawnattr_setexecfd_np() function sets the spawn-execfd attribute in an initialized attributes object referenced by attr.

The spawn-execfd attribute provides the file descriptor that is used to execute new image in the spawned process by the posix_spawn(3) family of functions. If the attribute is set to a value other then -1, it must be a valid file descriptor which does not have the O_CLOFORK flag set. Then, posix_spawn() executes the executable image referenced by the file descriptor in the newly created process, using the fexecve(2) system call. In this case, the path argument to posix_spawn() is ignored.

The default value for the spawn-execfd attribute is -1, which means that the executed image is specified by the path argument to posix_spawn().

RETURN VALUES

The posix_spawnattr_getexecfd_np() and posix_spawnattr_setexecfd_np() functions return zero.

SEE ALSO

posix_spawn(3), posix_spawnattr_destroy(3), posix_spawnattr_init(3), posix_spawnp(3)

STANDARDS

The posix_spawnattr_getexecfd_np() and posix_spawnattr_setexecfd_np() are FreeBSD extensions that first appeared in FreeBSD 16.0.