UNIX for Dummies Questions & Answers

I've got a script at the moment that looks like this:

Code:

if [ $submenunum -eq 6 ]
        then
                echo "How many hours would you like users to have logged in for? (single digits)"
                read hours
                tim=
                echo "These are the users who were logged in for $hours hours:"
                echo "$tim"
        fi

For the 6th option in this particular menu script I'm trying to get the following command:

Code:

last | grep '(02:'

to fetch from the last file all logins of a certain amount of hours, but I am trying to provoke the user to type in the particular amount of hours they want to see. So where I have the variable tim, I expected this to work:

Code:

tim=$(last | grep '(0$hours:')

but it doesn't seem to want to comprehend having an open bracket inside the grep, without a closed one. It does work without the brackets, but then shows not only the login lengths matching the hours, but also the actual timestamps aswell, which I don't want.

How can I make the grep work inside the variable?

Cheers for any help in advance, and since this is my first query here and may have some more, is it better to create a new topic each time or shall I continue to use this thread?

Code:

#!/bin/ksh

typeset -Z2 tim

tim=8
last |
grep '[(]'$tim:

oh. and new topic each new problem.