perl -i.bak -nlwe '$h{$_}++; if (eof) {print for sort { length($a) <=>
+ length($b) } keys %h}' junk.txt junk2.txt

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You forgot to reset %h between files, so the second file will get all of the first file's lines. See my prototype answer.

-- Randal L. Schwartz, Perl hacker
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In reply to •Re: Re: Using -i in oneliner with postprocessing by merlyn
in thread Using -i in oneliner with postprocessing by Anomynous Monk

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