XPmouseCol()
 Get and/or Set the Mouse column position
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   Function:   XPmouseCol()

               This function will return and optionally set the
               Column position of the Mouse.

   Syntax:     XPmouseCol([<nCol>])

   Arguments:  <nCol> is the Column to position the Mouse cursor.

   Returns:    the Current Column position in the normal Clipper
               range of 0..MaxCol().

   Usage:      * Set the Mouse at the first Column
               XPmouseCol(0)
               Mostly this function (and XPmouseRow()) will be used to
               inspect the current Mouse Cursor position.