It sounds to me like you want the MLDBM module. Using MLDBM, you tie your multi-level data structure to a db file on disk. When you make a change to the structure in memory, it updates it in the db on disk. Voila! Instant persistance for hashes of arrays of hashes of references to arrays of scalars! Or whatever.

An example of how to use it:

use MLDBM;
tie (%myhash, MLDBM, "filename", O_RDWR|O_CREAT, 0664);
%myhash = { one => [0, 1, 2], employee => {serial_num => 1, name => "b
+ob"}, mary => 7};
[download]

MLDBM uses Data::Dumper to do the serialization, and stores the resulting serialized structure into a db on disk.

Hope this is what you were looking for.

Alan