This works:

perl -pi -e 'BEGIN{undef$/};s/(.*)/<$1>/s' filename.txt

A couple of notes:

And... I guess that's it... I undefined $/ so that the file would be read all at once :-)

HTH

In reply to Re: multi-line in-place edits by cog
in thread multi-line in-place edits by Tuppence

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