gtk_main_quit and threads

[Günther Rapp <guenther rapp-informatik de>]

Who can help

I have infinite loop in a thread doing jobs in the background for the
main application.
When I want to exit from the main application with a destroy event  via
gtk_main_quit
or a button directly calling gtk_main.quit the GTK does not terminate
only the
window is deleted form the screen.
Have I to kill the thread also and how to do this process.
Has anybody experience with this.

Thanks for help
günther 
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