I am trying to run shoutcast on my shared hosting server (it runs Debian). Every once and a while the shoutcast server dies. I am not always there to turn it back on. Is there a way to create a script that if dies will start back up?

The outline for the script is:

shoutcast server
sleep 5
DSP Plugin

If this script dies how can I set it up so it restarts again in 30 seconds?

Thanks in advance!

I would do an infinite while loop in a bash script that does a grep on ps -A and if the the main process name disappears (I am assuming it does when it dies), it restarts it again asynchronously (with an appended &). After this check it sleeps for 5 to 30 seconds. You could run the server from this script initially.

You can use a respawn event in /etc/inittab, but that won't wait for 30 seconds. When the script dies, it would be restarted immediately.

As an example, here is how I keep the program "mythbackend" always running as userid "mythtv" when I'm at runlevel 2, 3, 4, or 5. If it ever dies (which it never does), then it would be restarted ("respawned") immediately. Here's the line I manually added to /etc/inittab:

I am on shared hosting. I doubt that I have access to the main inittab. Is their a way to do it and confine it to one bash script?

Thanks

Denes described how to do that in his/her post above. You could also use a cron job to check-and-restart, but you probably don't have access to cron on a shared host either. There's no such thing as a "personal inittab", so the inittab route would be out for you if you don't have priviledged access to the system. If you want to get fancy you could have a parent fork and exec a child (which is the actual server). The parent loops and waits on the child, and when the child terminates, a new one is forked. The high-level functional equivalent of a looping bash script as Denes described, but implemented differently.

Bash is easier then dealing with fork and exec and a c compiler for this type of application. Assuming your process name is Test located in the directory this script was run from, the code below will do it. You may want to echo date when it restarts just so you know when it happens.

#!/bin/sh
while true;
do
PROCESS=`ps -A | grep Test`
if [ "$PROCESS" = "" ]
then
# Not found - start process
./Test &
else
# Found it - don't do anything
fi
sleep 30
done

True ... but I wouldn't do it in C. I'd do it in PERL:
Might want to add a bit of error checking, but the above one-liner covers the basics.

You could just make a script:

Then you have an endless loop which you will have to 'kill' or ctrl-c to stop.