hush/miscutils/setsid.c
Pascal Bellard 21e8e8da64 libbb: introduce and use BB_EXECVP_or_die()
function                                             old     new   delta
BB_EXECVP_or_die                                       -      47     +47
time_main                                           1042    1043      +1
chrt_main                                            371     364      -7
ionice_main                                          292     282     -10
setsid_main                                           69      56     -13
nohup_main                                           236     223     -13
cttyhack_main                                        266     253     -13
chroot_main                                           94      81     -13
chpst_main                                           746     733     -13
timeout_main                                         297     279     -18
taskset_main                                         541     522     -19
vfork_child                                           67      45     -22
parse                                                975     953     -22
lpd_main                                             770     748     -22
launch_helper                                        192     170     -22
tcpudpsvd_main                                      1810    1782     -28
nice_main                                            190     156     -34
env_main                                             242     206     -36
run_command                                          221     174     -47
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 1/17 up/down: 48/-352)         Total: -304 bytes

Signed-off-by: Pascal Bellard <pascal.bellard@ads-lu.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2010-07-04 00:57:03 +02:00

50 lines
1.2 KiB
C

/* vi: set sw=4 ts=4: */
/*
* setsid.c -- execute a command in a new session
* Rick Sladkey <jrs@world.std.com>
* In the public domain.
*
* 1999-02-22 Arkadiusz Mickiewicz <misiek@pld.ORG.PL>
* - added Native Language Support
*
* 2001-01-18 John Fremlin <vii@penguinpowered.com>
* - fork in case we are process group leader
*
* 2004-11-12 Paul Fox
* - busyboxed
*/
#include "libbb.h"
int setsid_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int setsid_main(int argc UNUSED_PARAM, char **argv)
{
if (!argv[1])
bb_show_usage();
/* setsid() is allowed only when we are not a process group leader.
* Otherwise our PID serves as PGID of some existing process group
* and cannot be used as PGID of a new process group. */
if (setsid() < 0) {
pid_t pid = fork_or_rexec(argv);
if (pid != 0) {
/* parent */
/* TODO:
* we can waitpid(pid, &status, 0) and then even
* emulate exitcode, making the behavior consistent
* in both forked and non forked cases.
* However, the code is larger and upstream
* does not do such trick.
*/
exit(EXIT_SUCCESS);
}
/* child */
/* now there should be no error: */
setsid();
}
argv++;
BB_EXECVP_or_die(argv);
}