Rewrite the home program from Exercise 5 in Chapter 6 to use IFS to extract the home directory from /etc/passwd. What happens to the program if one of the fields in the file is null, as in

Question

steve:*:203:100::/users/steve:/bin/ksh
Here the fifth field is null (::).

Answer 1

IFS=":"

if [ $# -ne 1 ] ; then
echo "Usage: home account" ; exit 0
fi

while read a b c d e f g
do
if [ "$1" = "$a" ] ; then
echo Home directory for account $a is $f
fi
done < /etc/passwd