awk can match patterns

The common pattern of grep X | awk '{...}' can sometimes be shortened to awk '/X/ {...}' instead. I'm not super clear on the details of awk vs. grep regex syntax, but relatively basic patterns work unchanged.

For instance, when trying to print the names of packages on the system that have been removed but left their config files behind (they are in "residual config" state), this snippet embeds the subcommand:

dpkg -l | grep '^rc' | awk '{print $2}'

Moving the pattern into awk to avoid running grep, we get:

dpkg -l | awk '/^rc/ {print $2}'

I know I shouldn't worry about system calls and "extra" processes being forked, but some old habits die hard.