I'm trying to understand start_daemon in the following /etc/init.d/nagios-nrpe-server startup script:

  start)
        if [ "$INETD" = 1 ]; then
                exit 1
        fi
        log_daemon_msg "Starting $DESC" "$NAME"
        start_daemon -p $PIDDIR/nrpe.pid $NICENESS $DAEMON  -c $CONFIG -d $DAEMON_OPTS
        log_end_msg $?
        ;;

In particular, when I start this service it isn't writing a PID file as expected, thus the stop service nagios-nrpe-server command is not working (I need to manually kill the processes).

I'm trying to figure out how to trouble shoot the problem, but I can't run start_daemon ... from the command line.

I want to reproduce what the script is doing manually so I can work on what the problem is.