#!/bin/sh -u
#     $0   (no arguments)
# A script that presents a menu and lets you choose what to do.
#
# WARNING: Many of the comments in this file are "Instructor-Type"
#   comments and are *not* appropriate for real scripts.  Do not put
#   "Instructor-Type" comments into the scripts that you submit for marking.
#   I put them in my example files because I am teaching you how to
#   write scripts; do not submit my teaching comments back to me again.
#   Read the week7.txt notes for more details on good comment style.
#
# -IAN! idallen@ncf.ca   July 2001

# all scripts must start with lines similar to these two:
#
export PATH=/bin:/usr/bin
umask 022

# Note how the "echo" error message goes to Standard Error, and it
# includes the program name and the incorrect argument count, as
# well as the list of command line arguments.
#
if test "$#" -ne 0 ; then
	echo 1>&2 "$0: Expecting zero arguments.  You gave me $# ($*)."
	exit 1
fi

# If you want to make this script loop, uncomment this line and the
# matching 3 lines at the bottom of the script:
#
#while : ; do

# Clear your terminal screen, getting it ready for the nice menu.
#
clear

# This "Here" document is supplied to the given command as standard input.  
# The "cat" command simply displays standard input on standard output.
# Thus, this is a nice way of displaying several lines of text without
# using a whole bunch of "echo" commands (and lots of quotes!).
#
# The word EOF is unquoted, so the Here Document is processed by the
# shell as if it were a *double*-quoted string.  That means dollar
# variables are expanded inside this Here Document!
#
cat <<EOF

     Hello $USER, your menu choices are:

       1  The Date
       2  List of online users
       3  A count of accounts in the passwd file
       q  Do nothing - quit
     
     Enter your choice:
EOF

read choice

# It's often good to echo back any input typed by a user.
# It's very good to do it when debugging a shell script.
#
echo "Your choice was: $choice"

case "$choice" in
1)	date ;;
2)	who ;;
3)	wc -l /etc/passwd  ;;
[qQ])	echo "Goodbye!" ; exit 0 ;;
*)	echo 1>&2 "$0: Unrecognized menu choice '$choice'" ;;
esac

# If you want to make this script loop, uncomment these 3 lines and the
# matching "while" line in the middle of the script:
#
#echo "Press return to continue..."
#read junk
#done

exit 0