Dynamic update of handles within calls to an external function (e.g. abort button)

Hello, I have a gui that when a button is pushed it runs the program. I then have the ability to stop or pause the program (e.g. like pause/play/stop feature of a video).

My problem is that handles update dynamically for callback functions created in gui but do not update dynamically for externally created functions. Therefore, I can't get an abort or stop button to function when pressed. The external function only knows the value of the handle from the time before it was passed.

Either this hasn't been discussed (highly doubtful) or couldn't find an existing thread or did not recognize a presented solution as applicable to my problem (most likely).

Please help. Thanks!