FAQ 4.73 How do I keep persistent data across program calls?

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4.73: How do I keep persistent data across program calls?

    For some specific applications, you can use one of the DBM modules. See
    AnyDBM_File. More generically, you should consult the "FreezeThaw" or
    "Storable" modules from CPAN. Starting from Perl 5.8 "Storable" is part
    of the standard distribution. Here's one example using "Storable"'s
    "store" and "retrieve" functions:

            use Storable;
            store(\%hash, "filename");

            # later on...
            $href = retrieve("filename");        # by ref
            %hash = %{ retrieve("filename") };   # direct to hash


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