It's much faster than using Perl and File::ReadBackwards:

True if the only aim is to reverse the file.

If however, the aim is to process the data in the file in the reverse order using perl, you'd have to compare F::RB with using tac and then reading every record in the file using Perl.

Also, how many lines are there in your test file?

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In reply to Re^2: How to reverse a huge file in Perl? by BrowserUk
in thread How to reverse a huge file in Perl? by MelaOS

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