For the why:

> Can someone help to explain how this happen?

Perl's model for threading is to clone the interpreter with the data. It's allowing thread-safety by emulating forking.

The shared data is explicitly tunneled between the threads.

New data - including their refs - doesn't exist in other threads unless they are shared.

Hence using a backdoor like Devel::Pointer to the memory address can't work.

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

In reply to Re: use Devel::Pointer in threads by LanX
in thread use Devel::Pointer in threads by exilepanda

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