I think this question is a little more subtle because of the way Win32::TieRegistry uses tied hashes as an interface. It's not immediately obvious what happens if multi-level hash keys are used. You can do chaining as if it were a HoH structure, but the documentation seems to imply that the "autovivification" is temporary and is only reflected in the Perl data structure, not the underlying registry.

From the Pod:

        $tip18= $Registry->{"LMachine/Software/Microsoft/"}->
                  {"Windows/CurrentVersion/Explorer/Tips/"}->{"/18"};

    Like above, this creates intermediate key objects then uses them t
+o access other data. Once this statement finishes, the intermediate k
+ey objects are destroyed. Several handles into the Registry are opene
+d and closed by this statement so it is less efficient but there are 
+times when this will be useful.

[download]

-xdg

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In reply to Re^2: In Win32::TieRegistry, what is the best way to tell if a registry variable exists? (vivify) by xdg
in thread In Win32::TieRegistry, what is the best way to tell if a registry variable exists? by DrWhy

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