Waiting For A Thread To Exit

Since threads are also subroutines, they can return values.  To wait
for a thread to exit and extract any values it might return, you can
use the join() method:

    use threads;

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

    @ReturnData = $thr->join;
    print "Thread returned @ReturnData";

    sub sub1 { return "Fifty-six", "foo", 2; }

In the example above, the join() method returns as soon as the thread
ends.  In addition to waiting for a thread to finish and gathering up
any values that the thread might have returned, join() also performs
any OS cleanup necessary for the thread.  That cleanup might be impor-
tant, especially for long-running programs that spawn lots of threads.
If you don't want the return values and don't want to wait for the
thread to finish, you should call the detach() method instead, as
described next.
[download]

I think the problem with perlthrtut and some other bits of the documentation (what there is of it), was mostly written for 5005threads and hasn't really caught up with ithreads yet.

That said. I'm not sure how the snippet you quote would have worked then either.

---

Examine what is said, not who speaks.

"Efficiency is intelligent laziness." -David Dunham
"Think for yourself!" - Abigail
"Memory, processor, disk in that order on the hardware side. Algorithm, algoritm, algorithm on the code side." - tachyon

Patches are welcome. (Appreciated even.)

Just a wild idea: could the thread routine not provide the return result for all possible contexts (scalar, array, boolean, ...) and have the join routine pick the one it needs as per its own context?

CountZero

"If you have four groups working on a compiler, you'll get a 4-pass compiler." - Conway's Law