The Grab command works as follows: click on the Grab button in the XV controls window, or type a <ctrl-G> in any active XV window. The terminal will beep once, signifying the beginning of a Grab command. You can grab the entire contents of a window (including its frame) by clicking the Left mouse button in a window. If you click the Left button somewhere on the root window, the entire screen will be loaded into XV. You can grab an arbitrary region of the screen by clicking the Middle mouse button and dragging a rectangle.