If you don't want to modify $wholefile with a substitution, $wholefile_copy = $wholefile; and run substitution on the copy. Not trying to be snarky, but unless the file is humongous, the memory usage won't matter.

In reply to Re: Extracting data from file and modifying without making change in file. by Marshall
in thread Extracting data from file and modifying without making change in file. by tej

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