Shell Programming and Scripting

while [ -z "$var1" ]
do	printf 'Enter variable 1 value: '
	read -r var1
	[ -z "$var1" ] && echo 'Variable 1 cannot be empty; try again.'
done
while [ -z "$var2" ]
do	printf 'Enter variable 2 value: '
	read -r var2
	[ -z "$var2" ] && echo 'Variable 2 cannot be empty; try again.'

done
...

#!/bin/bash
#
#	Variables
#
	# Expand the task list with words that describe the task
	declare TASK_LIST="name email"
	declare -A ANSWERS
#
#	Messages
#
	# Use the words from the task-list as string identifier
	MSG_STR_NAME="What is your name"
	MSG_STR_EMAIL="What is your email"
#
#	Action
#
	# Work the list
	for task in $TASK_LIST
	do
		# Prepare the message string
		str=MSG_STR_${task^^}
		# Loop while input is empty
		while [ -z "${ANSWERS[$task]}" ]
		do
			echo ${!str}
			read input
			ANSWERS[$task]=$input
		done
	done
#
#	Your work to do....
#
	echo
	echo "Result values are:"
	for item in $TASK_LIST
	do
		echo "$item :: ${ANSWERS[$item]}"
	done

0 ~/tmp $ bash aravindadla 
What is your name
Simon
What is your email
something

Result values are:
name :: Simon
email :: something

First Name,FNAME  
Last Name,LNAME    
Birthday,BDAY

getvar() { while [ ! ${!2} ]; do read -p "$1: " "$2"; done }

while IFS=, read PR VAR <&3; do getvar "$PR" "$VAR"; echo $VAR"="${!VAR}; done 3< file
First Name: Joe
FNAME=Joe
Last Name: Miller
LNAME=Miller
Birthday: 12.7.88
BDAY=12.7.88