With binmode, what you have would work. 

perl -i.bak -pe "BEGIN { binmode STDOUT } s/(?=\[)/\r\n/g" file

[download]

Without binmode, \n gets transformed to CR+LF, so \r\n become CR+CR+LF. 

perl -i.bak -pe "s/(?=\[)/\n/g" file

[download]

Update: Escaped [ as noticed by Tanktalus.

In reply to Re: How to inject chr(10) chr(13) into a string by ikegami
in thread How to inject chr(10) chr(13) into a string by Mark Weimer

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