From a quick look at the Net::Pcap source, the return value of open_live() isn't a 'object', at least not in the Perlish sense of a blessed reference. It is the value returned from a direct call to the pcap c-library function: 

pcap_t *
pcap_open_live(device, snaplen, promisc, to_ms, err)
...
    RETVAL = pcap_open_live(device, snaplen, promisc, to_ms, errbuf);

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That looks like a c struct address to me. If that is the case, and that is what is ending up back in your Perl program, it ought to look like an unsigned integer to Perl. And if that were true, it is hard to see why Perl wouldn't let you assign it to a shared scalar.

Would you try assigning it to a non-shared variable, printing it and post the output here?

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
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In reply to Re: Shared variables between threads by BrowserUk
in thread Shared variables between threads by Saladino

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