Bernhard Reutner-Fischer | c89982d | 2006-06-03 19:49:21 +0000 | [diff] [blame] | 1 | /* vi: set sw=4 ts=4: */ |
Paul Fox | 4240364 | 2005-08-01 22:52:09 +0000 | [diff] [blame] | 2 | /* |
| 3 | * setsid.c -- execute a command in a new session |
| 4 | * Rick Sladkey <jrs@world.std.com> |
| 5 | * In the public domain. |
| 6 | * |
Denis Vlasenko | b44c790 | 2008-03-17 09:29:43 +0000 | [diff] [blame] | 7 | * 1999-02-22 Arkadiusz Mickiewicz <misiek@pld.ORG.PL> |
Paul Fox | 4240364 | 2005-08-01 22:52:09 +0000 | [diff] [blame] | 8 | * - added Native Language Support |
| 9 | * |
| 10 | * 2001-01-18 John Fremlin <vii@penguinpowered.com> |
| 11 | * - fork in case we are process group leader |
| 12 | * |
| 13 | * 2004-11-12 Paul Fox |
| 14 | * - busyboxed |
| 15 | */ |
| 16 | |
Denis Vlasenko | b6adbf1 | 2007-05-26 19:00:18 +0000 | [diff] [blame] | 17 | #include "libbb.h" |
Paul Fox | 4240364 | 2005-08-01 22:52:09 +0000 | [diff] [blame] | 18 | |
Denis Vlasenko | 9b49a5e | 2007-10-11 10:05:36 +0000 | [diff] [blame] | 19 | int setsid_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
Denis Vlasenko | a60f84e | 2008-07-05 09:18:54 +0000 | [diff] [blame] | 20 | int setsid_main(int argc UNUSED_PARAM, char **argv) |
Mike Frysinger | e1d41b3 | 2006-03-23 02:07:41 +0000 | [diff] [blame] | 21 | { |
Denis Vlasenko | b44c790 | 2008-03-17 09:29:43 +0000 | [diff] [blame] | 22 | if (!argv[1]) |
Paul Fox | 4240364 | 2005-08-01 22:52:09 +0000 | [diff] [blame] | 23 | bb_show_usage(); |
Paul Fox | 4240364 | 2005-08-01 22:52:09 +0000 | [diff] [blame] | 24 | |
Denis Vlasenko | b44c790 | 2008-03-17 09:29:43 +0000 | [diff] [blame] | 25 | /* setsid() is allowed only when we are not a process group leader. |
| 26 | * Otherwise our PID serves as PGID of some existing process group |
| 27 | * and cannot be used as PGID of a new process group. */ |
Denys Vlasenko | a29b055 | 2010-05-16 02:12:56 +0200 | [diff] [blame] | 28 | if (setsid() < 0) { |
| 29 | pid_t pid = fork_or_rexec(argv); |
| 30 | if (pid != 0) { |
| 31 | /* parent */ |
| 32 | /* TODO: |
| 33 | * we can waitpid(pid, &status, 0) and then even |
| 34 | * emulate exitcode, making the behavior consistent |
| 35 | * in both forked and non forked cases. |
| 36 | * However, the code is larger and upstream |
| 37 | * does not do such trick. |
| 38 | */ |
| 39 | exit(EXIT_SUCCESS); |
| 40 | } |
Paul Fox | 4240364 | 2005-08-01 22:52:09 +0000 | [diff] [blame] | 41 | |
Denys Vlasenko | a29b055 | 2010-05-16 02:12:56 +0200 | [diff] [blame] | 42 | /* child */ |
| 43 | /* now there should be no error: */ |
| 44 | setsid(); |
| 45 | } |
Paul Fox | 4240364 | 2005-08-01 22:52:09 +0000 | [diff] [blame] | 46 | |
Denys Vlasenko | 41ddd9f | 2010-06-25 01:46:53 +0200 | [diff] [blame] | 47 | argv++; |
Pascal Bellard | 21e8e8d | 2010-07-04 00:57:03 +0200 | [diff] [blame] | 48 | BB_EXECVP_or_die(argv); |
Paul Fox | 4240364 | 2005-08-01 22:52:09 +0000 | [diff] [blame] | 49 | } |