cpio
From Gentoo Wiki
cpio is a file archiving utility. It utilises a file format of the same name, cpio(5).
By default, Gentoo uses GNU cpio (gcpio) as its cpio implementation. However, app-arch/libarchive provides an alternative implementation, bsdcpio.
Emerge
root #
emerge --ask app-alternatives/cpio
Removal
Unmerge
root #
emerge --ask --depclean --verbose app-alternatives/cpio