Using SHELL to get a list of processes

Mark Schonewille m.schonewille at
Thu Feb 5 14:25:25 EST 2009

Hi Hugh,

If you want to run only one instance of your standalone at a time, you  
need to include a relaunch handler in your stack script. Assuming that  
you want the existing instance to come to the foreground when the  
second instance is launched and that you want the second instance to  
quit immediately, all you need is to catch the message and not pass it:

on relaunch
   return empty -- just for clarity, if you like
end relaunch

If you return "background", the second instance is terminated, but the  
first instance won't be activated. If you pass the message, the second  
instance will run.

Best regards,

Mark Schonewille

Economy-x-Talk Consulting and Software Engineering
Dutch forum:

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discuss your custom software project!

On 5 feb 2009, at 19:55, Hugh Senior wrote:

> Goal:
> Using shell()to determine if my Rev app is among the line of all  
> running
> processes. If so, then user has started a second instance and I want  
> to
> quit.
> Task 1: Get a list of all running processes and IDs.
> Task 2: Get the process name and ID of my Rev app.
> With me so far? Okay...
> I should be able to get a list of all running process using "ps -e"
> (according to
> So I try this in the message box, hoping to see some sort of a list:
> answer shell("ps -e")
> What I get instead is 'ps is not recognised as an internal or external
> command, operable program or batch file.'
> Same result using shell("top") and shell("list-processes").
> So what stupidity am I doing, please (apart from naively expecting the
> syntax to work)? And how do I get the process name & ID of the app?
> /H

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