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Why don't you use the sliding window technique already discussed?
window |------[++++++|++++++]------|------|---| file A B C D E F blocks <-----> match

If you don't destroy/recreate the variables but just change the content, your memory consumption will be minimal.

seek and read help reading chunks of data from files.

substr manipulates the content of strings.

pos returns the position of your last regex match.

So only one global variable $window of fixed size holding two current blocks could do and whenever the pos of a match leaves the first block you have to shift a new block into $window.

Cheers Rolf

) well, as long as Perl doesn't do very (unlikely) weird speed optimizations.


This code is an almost perfect example of what I meant: Matching in huge files

The differences are the temporary variable $block which could be optimized away and the handling of pos. Instead of adjusting the window at "halftime", pos is adjusted to the window. Actually I think this is even smarter than what I planed...

In reply to Re: Memory Leak when slurping files in a loop by LanX
in thread Memory Leak when slurping files in a loop by rizzy

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