A question...

I'm looking for some way to to automate the following process..

I've written a very simple script that runs four instances of the ps -ef |grep -i xxxx command with different xxxxs ( i.e. search strings ) in each line. The output of this, ofcourse is a listing of all these processes running with xxxx included.

My problem is the following:

I need to be able to a) Set a timer that will let the script be run autiomatically every say 20 minutes.
and b) I need to be able to set a check, returning a confirmation message as to whether the process xxxx is running or not ( as opposed to a listing of the processes ) Meaning, if the process xxxx IS running, I get an echo saying "Process xxxx is up and running".

I've been thinking of later incorporating a menu, that will allow me to check each process one by one based on user choice, but first this is more necessary. Any help will be appreciated.

Cheers