If you run a Linux box, and you want to see what services start up at which level, you use runlevel:

$ chkconfig
acpid           0:off   1:off   2:on    3:on    4:on    5:on    6:off
atd             0:off   1:off   2:off   3:on    4:on    5:on    6:off
auditd          0:off   1:off   2:on    3:off   4:off   5:off   6:off
blk-availability        0:off   1:on    2:on    3:on    4:on    5:on    6:off
cpuspeed        0:off   1:on    2:on    3:on    4:on    5:on    6:off
crond           0:off   1:off   2:on    3:on    4:on    5:on    6:off
cups            0:off   1:off   2:on    3:off   4:off   5:off   6:off
...

Boy is that hard to read at a glance. All the “on” and “off” look very similar to each other, and that blk-availability service’s length screws up the tabbed columns. I decided I needed a better way, which I called cclist.

$ cclist
  2345  acpid
   345  atd
  2     auditd
 12345  blk-availability
 12345  cpuspeed
  2345  crond
  2     cups
...

Here’s the code to ~/bin/cclist:

#!/usr/bin/perl

open( my $fh, '/sbin/chkconfig --list |' ) or die "Can't open chkconfig: $!";

while (<$fh>) {
    if ( /^(\S+)(\s+\d:o(n|ff)){7}/ ) {
        chomp;
        my @cols = split;
        my $service = shift @cols;
        for ( @cols ) {
            my ( $level, $status ) = split /:/;
            print $status eq "on" ? $level : " ";
        }
        print "\t$service\n";
    }
    else {
        print;
    }
}