On the threadA you are putting shift into $Qab. What is this doing? I am assuming it is to put the parameter into the sub's $Qab, but correct me if I am wrong.

Correct. A thread function is just a normal function that takes it arguments in the normal way.

Also what role does $Qab->enqueue( undef );

Once threadA has finished its loop; it queues undef before terminating. That undef causes the while loop in threadB to terminate; whence it then enqueues undef which cause the while loop in threadC to terminate.

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In reply to Re^3: Data Between Threads by BrowserUk
in thread Data Between Threads by UpTide

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