libbb: use _exit, not exit, in bb_daemonize_or_rexec()

By the time we reach exit in parent, child already exited or execed.
We should not re-run libc cleanup code.

While at it, introduce bb_daemon_helper() and add a few comments.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/loginutils/login.c b/loginutils/login.c
index 381468d81..fcdb9592c 100644
--- a/loginutils/login.c
+++ b/loginutils/login.c
@@ -350,8 +350,8 @@ int login_main(int argc UNUSED_PARAM, char **argv)
 	/* Mandatory paranoia for suid applet:
 	 * ensure that fd# 0,1,2 are opened (at least to /dev/null)
 	 * and any extra open fd's are closed.
-	 * (The name of the function is misleading. Not daemonizing here.) */
-	bb_daemonize_or_rexec(DAEMON_ONLY_SANITIZE | DAEMON_CLOSE_EXTRA_FDS, NULL);
+	 */
+	bb_daemon_helper(DAEMON_CLOSE_EXTRA_FDS);
 
 	username[0] = '\0';
 	opt = getopt32(argv, "f:h:p", &opt_user, &opt_host);