high priority interupt event

["Richard Tyc" <richt(at)sbrc.umanitoba.ca>]

Is there any way to send a high priority event, say from an button widget,
and have it interrupt time consuming processes like draws ?

Our  IDL application controls some servo motors via socket coomunication.
When the app is "executing" a process, the procedure goes into a loop and I
do check for other events at the beginning of this loop :

    ev = WIDGET_EVENT(sState.wEStop, /NOWAIT)

and then check a common block variable to see if the estop button was
pressed.

But, later in the loop, a   sState.oWindow->Draw,sState.oView is issued
which can take minutes.  Can I somehow break this call if the estop button
was pressed ??
Something like raising a signal and catching it in a handler ?

Thanks in advance

Rich