equery

View information about Portage packages. More information: https://wiki.gentoo.org/wiki/Equery.

List all installed packages:

equery list '*'

Search for installed packages in the Portage tree and in overlays:

equery list -po {{package_name}}

List all packages that depend on a given package:

equery depends {{package_name}}

List all packages that a given package depends on:

equery depgraph {{package_name}}

List all files installed by a package:

equery files --tree {{package_name}}