MRIGHTDOWN()
 Determine the status of the right mouse button
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 Syntax

     MRIGHTDOWN() --> lIsPressed

 Returns

     MRIGHTDOWN() returns true (.T.) if the mouse's right button is currently
     pressed; otherwise, it returns false (.F.) .

 Description

     MRIGHTDOWN() determines the button press status of the right mouse
     button.  This function is provided in the interest of completeness
     since, on the PC, the right mouse button is typically reserved for
     single-click oriented activities such as activating a pop-up menu.