Bashing on your door again!!

jay2901 · 08-07-2004, 09:32 AM

I am trying to get a test piece of code working, it is based around a simple menu system. I can not get a while loop to work within another while loop. Can you answer my question? And if you find the answer to that one can you tell me how to use the || operator so I can catch both uppercase and lowercase for "Y" and "y" in the menu.

Thank you in advance, here's the code not very exciting, just a tester for the while loop:

Code:

#!/bin/bash

flag="1"
while [ "$flag" -eq "1" ]; do
	clear
	echo "in the main menu"
	echo "EMPLOYEE DATA PROGRAM"
	echo "---------------------"
	echo " "
	echo "1. Add employee details"
	echo "2. View a list of employees"
	echo " "
	echo "Q. Quit"
	echo " "
	echo -n "Enter an option (1/2/Q) > "
	read MenuOpt
	case $MenuOpt in
		"1")
			again="y"
			while [ "$again" -eq "y" ]; do
			again=""
			echo " "
			echo "EMPLOYEE DATA PROGRAM - (Add Details)"
			echo "-------------------------------------"	
			echo " "
			echo -n "Enter employee's first name > "
			read FirstName
			echo -n "Enter employee's age > "
			read age
			echo "$FirstName" "$age" >> /home/jay/employees.dat	
			echo -n "Do you want to enter another > "
			read again
			done
			;;
		"2")
			clear 
			echo "View a list of employees"
			echo -n "Enter any character to continue > "
			read dummy
			;;
		"q")
			flag="0"
			;;
		"Q")
			flag="0"
			;;
		*)
			clear
			echo "Enter the correct selection"
			echo -n "Enter any letter to continue > "
			read dummy
	esac
	clear
done

jlliagre · 08-07-2004, 09:55 AM

You're confusing "-eq" that means numerically equal with "=" that check string equality, so

Code:

while [ "$again" -eq "y" ]; do

should be

Code:

while [ "$again" = "y" ]; do

or

Code:

while [ "$again" = "y" -o "$again" = "Y" ]; do

You can also use "==" instead of "=", just to be more consistent with other languages like C where "=" is reserved for assignation.

Don't confuse "||" from "-o", the former is to use between shell commands while the latter is for combining test (aka "[") clauses.

david_ross · 08-07-2004, 10:07 AM

I would usually use "==" for the while loop. Including OR it would be:

Code:

			while [ "$again" == "y" ] || [ "$again" == "Y" ]; do

For the OR in case:

Code:

		Q|q)
			flag="0"
			;;

jay2901 · 08-07-2004, 10:25 AM

This site as got the most helpful people on the planet, I swear!! Thanks guys!