comm(1) on Linux
The text c28ec8cd754a, as Debian 11 (Bullseye) shipped it.
compare two sorted files line by line
Flags it lists
-
--check-order -
--help -
--nocheck-order -
--output-delimiter -
--total -
--version -
--zero-terminated -
-1 -
-2 -
-3 -
-z