XPgetTimer()
  Return the elapsed time in seconds.
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  Function:    XPgetTimer()

               GetTimer returns the elapsed seconds since the
               last call to XPstartTimer(). There is no need to
               keep temporary variables or whatever to keep track
               of the Timer variables. See XPtimerStr() for an
               ASCII equivalent of this function.

  Syntax:      XPgetTimer().

  Arguments:   None.

  Returns:     A numerical, number of seconds (No distinction for
               minutes, hours etc..).

  Usage:       * - See XPstartTimer().