int pascal WinSetSize(HWND hWnd, int height, int width)

  This function changes the size of the specified window. This
function will send a WM_SIZE message to the window's window procedure
in order to give the application a chance to make any adjustments to
reflect the new size of the window. WinSetSize() does no redrawing on
its own. You should not do any drawing in response to the WM_SIZE
message either. Instead, you should call WinDrawAllWindows() or
ShowWindow() in order to redraw your application after all of the
various resizing is done.

Parameters
  hWnd is the handle of the window to resize.
  height and width are the new dimensions of the window.

Returns
  This function returns whatever the window's window procedure returns
when it gets the WM_SIZE message.