One option to avoid slurping and would be to set $/ to the double return:

perl -i -pe 'BEGIN{$/="\n\n"} s/\n\n/\n/;' foo.txt

Another option would be to set $/ and $\ (Yay, output format!) and chomp it:

perl -i -pe 'BEGIN{$/="\n\n";$\="\n"} chomp;' foo.txt

-i added back in per kyle's post. Also, ++ to ikegami, too!

--
$you = new YOU;
honk() if $you->love(perl)

In reply to Re^2: how to use matching operator on newlines by extremely
in thread how to use matching operator on newlines by redss

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