First of all make.sure the results fit, thus grep doesn't take $.as regex meta symbol!!!

Than I seen to remember problems with end of line localization and or Unicode

Please check the encoding for \n in your file and your Perl.

HTH! :)

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

In reply to Re^5: 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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