Ahh! You are combining read with readline ...

 $_ .= <$fh> // ''; # finish partial line

That's a good trick!

(As long as a line doesn't become bigger than memory, but that's hardly the case here.)

Cheers Rolf
(addicted to the Perl Programming Language and ☆☆☆☆ :)
Je suis Charlie!

In reply to Re^4: How to optimize a regex on a large file read line by line ? by LanX
in thread How to optimize a regex on a large file read line by line ? by John FENDER

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