Runn apps and close them on exit

Hello,

Changed the topic and my post - thinks this should be easier to answer.

How can I call an external .exe and get the process ID it is running under?
I would like to do something of this kinde:
Exec "C:\myapp\doit.exe"
Pop $processID
; do something else...
; on installer-exit:
KillProcess $processID

Thanks in advance!

If running application has window title and/or window class, you may use this function.
Also check FCT plugin and nsProcess plugin.

Thank you so far, I will look into this.
But isn't there any "internal" variable/function that holds the procesid for processes started by Exec?