| 
            plxormod
          ( | mode , | 
| status ); | 
      Enter (when 
         is true)
      or leave (when mode
      
         is false)
      xor mode for those drivers
      (e.g., the xwin driver) that support it.  Enables erasing plots by
      drawing twice the same line, symbol, etc.  If driver is not capable
      of xor operation it returns a
      mode
      
         of false.
    status
      
mode
          (PLBOOL
            modemode
status
          (PLBOOL_NC_SCALAR
            Returned value of the status.
            mode
      Redacted form: plxormod(mode, status)
    
This function is used in examples 1 and 20.