#!/bin/bash
WHEN=`date +%Y`
RC=0
while [ $RC -ne 103 ]
do
  PREV=`expr $WHEN - 1`
  NEXT=`expr $WHEN + 1`

  cal $WHEN | xmessage -buttons $PREV,$NEXT,Quit -file - -title "In the Year $WHEN"

  RC=$?
  case $RC in
  101) WHEN=$PREV
     ;;
  102) WHEN=$NEXT
     ;;
  *) RC=103
     ;;
  esac
done
exit 0
==== SNIP HERE =====

Part 2 is my blackbox menu, which invokes the Xcal script. The part of my
blackbox menu that invokes the script looks like...

