I am the original poster and have just joined perlmonks. Thanks so much for the advice. I have now gotten it working in the main program.

Just want to be sure I am correctly understanding what is going on. You can't actually pass a value from a subroutine to the main program using a button or other widget. Instead, you create a reference to the value of interest in the main program, send that reference to the subroutine and change the reference value in the subroutine. That changed value can then be accessed from the main program. Correct?

In reply to Re^2: Perk Tk - how to send a value from a subroutine back to the main program using Button by jeri_rl
in thread Perk Tk - how to send a value from a subroutine back to the main program using Button by Anonymous Monk

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