I think it is a documentation problem in perlthrtut. The documentation of threads->join states specifically:
$thread->join
This will wait for the corresponding thread to join. When the thread finishes, join() will return the return values of the entry point function. If the thread has been detached, an error will be thrown.

The context (scalar or list) of the thread creation is also the context for join(). This means that if you intend to return an array from a thread, you must use "my ($thread) = threads-"new(...)>, and that if you intend to return a scalar, you must use "my $thread = ...".

Applied to your example, this would mean: 

($thr) = threads->new(\&sub1);

[download]

Liz

Update:
Apparently the above documentation is in 5.8.1, and not in 5.8.0. I guess you could say it's one more documentation bug that was fixed by 5.8.1. Sorry for the possible confusion.

In reply to Re: threads->join by liz
in thread threads->join by powerman

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