[LAU] another scripting question

[Dave Phillips]

Greetings,

I'd like to add some conditional tests to my simple scripts. For 
example, I want to query the system to determine whether JACK is already 
running. If it is, I'll run an app (e.g. xine or AlsaPlayer) configured 
for JACK. If JACK is not running, I'll run the app without it.

So how do I test for JACK in a simple bash shell script ?

Similarly, I'd like to display an option to launch JACK if it isn't 
already running, but I think I can figure that one for myself. :)

Best,

dp