What's a simple way to get a Perl script to run as a daemon in linux?
Currently, this is on CentOS. I'd want it to start up with the system and shutdown with the system, so some /etc/rc.d/init.d
integration would also be nice, but I could always add a custom line to /etc/rc.d/rc.local
.
The easiest way is to use Proc::Daemon.
#!/usr/bin/perl
use strict;
use warnings;
use Proc::Daemon;
Proc::Daemon::Init;
my $continue = 1;
$SIG{TERM} = sub { $continue = 0 };
while ($continue) {
#do stuff
}
Alternately you could do all of the things Proc::Daemon does:
"/"
.Integrating with the runlevel system is easy. You need a script like the following (replace XXXXXXXXXXXX
with the Perl script's name, YYYYYYYYYYYYYYYYYYY
with a description of what it does, and /path/to
with path to the Perl script) in /etc/init.d
. Since you are using CentOS, once you have the script in /etc/init.d
, you can just use chkconfig to turn it off or on in the various runlevels.
#!/bin/bash
#
# XXXXXXXXXXXX This starts and stops XXXXXXXXXXXX
#
# chkconfig: 2345 12 88
# description: XXXXXXXXXXXX is YYYYYYYYYYYYYYYYYYY
# processname: XXXXXXXXXXXX
# pidfile: /var/run/XXXXXXXXXXXX.pid
### BEGIN INIT INFO
# Provides: $XXXXXXXXXXXX
### END INIT INFO
# Source function library.
. /etc/init.d/functions
binary="/path/to/XXXXXXXXXXXX"
[ -x $binary ] || exit 0
RETVAL=0
start() {
echo -n "Starting XXXXXXXXXXXX: "
daemon $binary
RETVAL=$?
PID=$!
echo
[ $RETVAL -eq 0 ] && touch /var/lock/subsys/XXXXXXXXXXXX
echo $PID > /var/run/XXXXXXXXXXXX.pid
}
stop() {
echo -n "Shutting down XXXXXXXXXXXX: "
killproc XXXXXXXXXXXX
RETVAL=$?
echo
if [ $RETVAL -eq 0 ]; then
rm -f /var/lock/subsys/XXXXXXXXXXXX
rm -f /var/run/XXXXXXXXXXXX.pid
fi
}
restart() {
echo -n "Restarting XXXXXXXXXXXX: "
stop
sleep 2
start
}
case "$1" in
start)
start
;;
stop)
stop
;;
status)
status XXXXXXXXXXXX
;;
restart)
restart
;;
*)
echo "Usage: $0 {start|stop|status|restart}"
;;
esac
exit 0