Here's a Perl 6 solution, works with current Rakudo. Not really golfed, just the way you'd write it in a terse way: 
$ cat /etc/passwd | perl6 -e '.say for lines.sort: +*.split(":")[2]'

[download]

The nice part is that Perl 6's sort method automatically does the Schwartzian transform for you if the comparison code object takes only one argument.

Perl 6 - the future is here, just unevenly distributed

In reply to Re: Golf: reverse sort /etc/passwd by UID by moritz
in thread Golf: reverse sort /etc/passwd by UID by Tommy

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