Patch from Russ Dill <Russ.Dill@asu.edu>. From the

start-stop-daemon man page:

-b|--background
        Typically used with programs that don't detach on their own.
        This option will force start-stop-daemon to fork before starting
        the process, and force it into the background. WARNING:
        start-stop-daemon cannot check the exit status if the process
        fails to execute for any reason. This is a last resort, and is
        only meant for programs that either make no sense forking on
        their own, or where it's not feasible to add the code for it to
        do this itself.

This is usefull for applets like watchdog


git-svn-id: svn://busybox.net/trunk/busybox@4112 69ca8d6d-28ef-0310-b511-8ec308f3f277

1 files changed, 10 insertions, 1 deletions

diff --git a/init/start_stop_daemon.c b/init/start_stop_daemon.c
index c6b704329..ed4503caf 100644
--- a/init/start_stop_daemon.c
+++ b/init/start_stop_daemon.c
@@ -22,6 +22,7 @@
 
 static int start = 0;
 static int stop = 0;
+static int fork_before_exec = 0;
 static int signal_nr = 15;
 static int user_id = -1;
 static const char *userspec = NULL;
@@ -55,7 +56,7 @@ parse_options(int argc, char * const *argv)
         int c;
 
         for (;;) {
-            c = getopt (argc, argv, "a:n:s:u:x:KS");
+            c = getopt (argc, argv, "a:n:s:u:x:KSb");
                 if (c == EOF)
                         break;
                 switch (c) {
@@ -81,6 +82,9 @@ parse_options(int argc, char * const *argv)
                 case 'x':
                         execname = optarg;
                         break;
+                case 'b':
+                        fork_before_exec = 1;
+                        break;
                 default:
                         show_usage();
                 }
@@ -255,6 +259,11 @@ start_stop_daemon_main(int argc, char **argv)
                 return EXIT_SUCCESS;
         }
         *--argv = startas;
+        if (fork_before_exec) {
+                if (daemon(0, 0) == -1)
+                        perror_msg_and_die ("unable to fork");
+        }
+        setsid();
         execv(startas, argv);
         perror_msg_and_die ("unable to start %s", startas);
 }