Hi RenMcCourtey,

Because by default ^ and $ only match at the beginning and end of the string, not each line within the string (I'm simplifying a little here - for the details see ^, $, and the /m modifier in perlre). This works:

perl -p0e 's/\n^\s*$//mg' input.txt
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But requires you to read the entire file* into memory. I'd use:

perl -ne 'print if /\S/' input.txt
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Hope this helps,
-- Hauke D

* assuming it doesn't contain NUL characters