twMsgEnd()
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     Clears the message stack and closes the associated windows of any
     message stack memory left.

     NOTE: The TSDWIN message class uses the Window Class to allocate
     screen memory. The message stack should be cleared immediately
     after use is using the -1 'Wait' parameter. If any other windows
     are opened before you do this, minor chaos can result in the
     window stack.

       Arguments:

     NONE

       Return:

     NIL

       Example:

     twMsgEnd()