As it's pure perl, I installed File::ReadBackwards locally and it's definitely the way to go - very impressive - only 90seconds to reverse the 180MB file and uses less than 5MB of memory to do it.

I diff'd the original .txt file with the .rev.rev file and no differences, so it seems to work ok!

problem solved - once again - many many thanks!

In reply to Re^2: Reversing A File by camelcom
in thread Reversing A File by camelcom

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