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  vupdatewindow                                                         WNDWC
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  Function       Updates the current virtual window including the view,
                 titles and the cursor.  It is also updated no matter where
                 its location even if hidden or overlapped.
  Syntax         void vupdatewindow(void);
  Remarks        This is the main routine to update virtual windows.  This
                 routine simply executes three procedures: vupdatecursor,
                 vupdateview, and vupdatetitles.  Works in any "writeto"
                 mode.
  Return value   None.
  Heap           If covered, wsrows * wcols * 5 bytes is temporarily used.