Fortunately, the manpage for comm comes through:

-1 ignores what's just in file 1
-2 ignores just what's in file 2
-3 ignores what's common to *both* files.

Oh! but... comm needs sorted input! Fortunately we already know about that though, so

comm <(sed ... | sort | uniq) <(egrep ... | sort | uniq)

Sorts that all out.

#shell #sort #uniq #linux #comm #PunInTenDid