For a homework assignment, I need to use grep to parse /etc/passwd and get a list of all users (their usernames only, nothing else). It should use a pipe, and the results should end up in the allusers ...
I'm looking for an easy, portable way to validate the number of fields in /etc/passwd, /etc/shadow, /etc/group and /etc/master.passwd. This would run on FreeBSD, Linux and other Un*xes. pwck does ...