Launching a subprocess under OSX?

Phil Davis revdev at
Thu Dec 29 15:23:29 EST 2016

Hi Paul,

In the Mac world, I find that if my app starts a true command-line tool 
(like SOX or FFMPEG or mediainfo) with 'open process' or 'shell()', all 
is well - no indication of its execution is visible to the user of my 
app. Of course those tools are designed to be command-line only - no 
bundle, no built-in UI.

If, on the other hand, my app launches a document with Word, I do see 
Word active in the Dock. And Word is a regular app bundle, unlike the 
command-line tools I mentioned.

Don't know if there is a definite relationship between the helper app's 
internal structure and its visibility in the Dock when running, but I 
thought I would at least share my experience.

Maybe there's a setting you can fiddle with in the helper app's plist 
that would make it run invisible? (Sounds like a potential can of worms 
but it might work)

Thanks -
Phil Davis

On 12/29/16 11:44 AM, Paul Dupuis wrote:
> On Windows, I can launch a subprocess using:
> open process tHelperApp for text update
> And I get a subprocess that does not appear as a separate running app to
> the user. They do not see it appear in the task bar. There is no
> apparent change to the running app that launched the helper. It just
> shows up in task list if you bring up the task manager with CTRL-ALT-DEL
> which is fine.
> On OSX (10.9.5), both 'launch thelperApp' and 'open process tHelperApp
> for text update' start the helper app but also brings it to the front
> (active app - you can see its menu - only the Apple and App name default
> menus) and it appears in the dock. This is undesirable.
> Does any one know how to launch a real subprocess under OSX from
> LiveCode that stay hidden or in the background at least?
> _______________________________________________
> use-livecode mailing list
> use-livecode at
> Please visit this url to subscribe, unsubscribe and manage your subscription preferences:

Phil Davis

More information about the Use-livecode mailing list