Just as an addition to the OP comment: "perl -pe 's/old/new/g'" is the perl pendant for sed. The obvious advantage is the support for Perl regexes. Also there'

Just as an addition to the OP comment: "perl -pe 's/old/new/g'" is the perl pendant for sed. The obvious advantage is the support for Perl regexes. Also there's the "-r" switch for sed which extends Regexes compatibility.