We should always be using _exit() after a fork() or vfork() instead of exit().

This is because exit() does some extra cleanup which in some implementations
of vfork(), for example, can actually modify the state of the parent process,
causing very weird bugs or crashes.  (issue #7971, Nick Gavrikov)


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.2@46361 65c4cc65-6c06-0410-ace0-fbb531ad65f3

apps/app_externalivr.c

@@ -324,7 +324,7 @@ static int app_exec(struct ast_channel *chan, void *data)
 			close(i);
 		execv(argv[0], argv);
 		fprintf(stderr, "Failed to execute '%s': %s\n", argv[0], strerror(errno));
-		exit(1);
+		_exit(1);
 	} else {
 		/* parent process */
 		int child_events_fd = child_stdin[1];

asterisk.c

@@ -449,7 +449,7 @@ int ast_safe_system(const char *s)
 		for (x = STDERR_FILENO + 1; x < 4096; x++)
 			close(x);
 		execl("/bin/sh", "/bin/sh", "-c", s, NULL);
-		exit(1);
+		_exit(1);
 	} else if (pid > 0) {
 		for(;;) {
 			res = wait4(pid, &status, 0, &rusage);

res/res_agi.c

@@ -297,7 +297,7 @@ static int launch_script(char *script, char *argv[], int *fds, int *efd, int *op
 		/* unblock important signal handlers */
 		if (sigfillset(&signal_set) || pthread_sigmask(SIG_UNBLOCK, &signal_set, NULL)) {
 			ast_log(LOG_WARNING, "unable to unblock signals for AGI script: %s\n", strerror(errno));
-			exit(1);
+			_exit(1);
 		}
 
 		/* Close everything but stdin/out/error */
@@ -308,7 +308,7 @@ static int launch_script(char *script, char *argv[], int *fds, int *efd, int *op
 		execv(script, argv);
 		/* Can't use ast_log since FD's are closed */
 		fprintf(stderr, "Failed to execute '%s': %s\n", script, strerror(errno));
-		exit(1);
+		_exit(1);
 	}
 	if (option_verbose > 2) 
 		ast_verbose(VERBOSE_PREFIX_3 "Launched AGI Script %s\n", script);

res/res_musiconhold.c

@@ -463,7 +463,7 @@ static int spawn_mp3(struct mohclass *class)
 		}
 		ast_log(LOG_WARNING, "Exec failed: %s\n", strerror(errno));
 		close(fds[1]);
-		exit(1);
+		_exit(1);
 	} else {
 		/* Parent */
 		close(fds[1]);