Question about an earlier post (Hash of Hashes Shared Across Parallel Forks Orphans Memory).

I had the same problem with IPC::Shareable as the person in the above-mentioned post, namely orphaned memory with IPC::Shareable. I side-stepped it by using an array instead of a hash. But frankly, I don't understand why that would help. And how/why does the mentioned solution improve things?

Maybe an answer will help with my current problem as well, but in case it doesn't: I have a loop which is supposed to add to said array, but if it ends up empty, the program dies with

Can't use an undefined value as an ARRAY reference at .../Shareable.pm line 446.

at the simple check

if (@array) {...}

Why can't I check if the array is empty? Here's a very short version of what I have:

use IPC::Shareable (':lock');

my @arr;
my %options = (
                 create => 'yes',
                 mode => 0644,
                 exclusive => 0,
                 destroy => 'yes'
               );
my $handle = tie @arr, 'IPC::Shareable', 'dat1', { %options } or die "
+Tie failed.\n";

#...

if (@arr) {
    #...
}

[download]

What do I need to change to make this work? Any help would be very much appreciated.

In reply to undefined value and orphaned memory with IPC::Shareable by dime

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