Lookup tool for domain names and other internet resources
https://packages.debian.org/sid/whois Formula was removed
Last versions were
whois requires the following formula to be installed:
xz 5.2.3 General-purpose data compression with high compression ratio

Recent formula history

FX Coudert Export formulae to homebrew/core.
ilovezfs whois 5.2.15
ilovezfs whois 5.2.14
ilovezfs whois 5.2.13
Shaun Jackman whois: fix for Linux (#610)

Formula code at GitHub