If you don't really need a fair shuffle, you could get around the memory limitations by simply process the file by parts. Do a fair shuffle on each of the parts, and cat them together in random order.
For better results, do this a number of times using a non-zero offset.

Of course, you won't have a real fair shuffle, but maybe this is good enough.

Hope this helps, -gjb-

In reply to Re: Randomize lines with limited memory by gjb
in thread Randomize lines with limited memory by natch

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