That only sorts @emails by domains.

Quite admittedly. But to quote the original poster:

How do I alphabetize a list of email addresses by domain?

..but I can quite see your point. Anyways, you'll want to plonk an "or" between your two lines of code so that it compiles. :)

Depending on how much the anonymous monk cares, they may or may not want to go whole hog and use Zaxo's more precise and tolerant answer.

perl -pe '"I lo*`+$^X$\"$]!$/"=~m%(.*)%s;$_=$1;y^`+*^e v^#$&V"+@( NO CARRIER'