For example, perhaps it might be better to convert the hash to a string (using Data::Dumper) and it is the string that is stored in the shared-memory segment.

Personally, I use JSON to store my data. I like the ease of it, and its especially good because it's cross platform and stores well in files if you want to dump the data for future program runs. Here's a non-complete example:

use warnings;
use strict;

use JSON;

my $shared_memory_variable = ...; # Create shared mem with IPC::Sharea
+ble

my $data = {
    a => 1, 
    b => [
        1, 
        2, 
        3
    ], 
    c => {
        z => 99, 
        y => 98, 
        x => {
            m => 'hello, world!'
        },
    },
};

# Create JSON string and store it in the shared memory allocation

$shared_memory_variable = encode_json $data;

# Restore the shared memory JSON to a Perl data structure

my $perl = decode_json $shared_memory_variable;
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