You can try Tie::File (https://perldoc.perl.org/Tie/File.html) 

The file is not loaded into memory, so this will work even for giganti
+c files.

Changes to the array are reflected in the file immediately.

[download]

In reply to Re: Fastest way of changing the beginning of a txt file.. by pwagyi
in thread Fastest way of changing the beginning of a txt file.. by pedrete

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