I have a doubt about threading basics. If I launch a new thread T1, the main thread has to wait for T1 to join or can continue its execution without waiting?.
If it has to wait, can I make both the main and the new threads run asynchronously?.
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If you does not call join() both thread executes concurrently. By default threads runs asynchronously. join() blocks the calling thread until a thread terminates.
I would like to add to make thread execute synchronised, concurrency control mechanisms are provided.
One can explore about POSIX Threads Programming
Grijesh Chauhan
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Hi!. So, if I put in my code `t1.join()` the main thread will have to wait for it, right?. Thanks!. – Kio Marv Dec 07 '12 at 10:51
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1yes, if in main thread you calls `ti.join()` then main thread will waits. – Grijesh Chauhan Dec 07 '12 at 10:53
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Another little point, if I don't use `join()`, once the thread has finished the computation, it will reunite with the main thread on its own, isn't it?. I mean, it will destroy itself once is done. And what if the main thread finished before the other one?. Then this will end in undefined behaviour, right?. Thanks. – Kio Marv Dec 07 '12 at 11:08
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If main thread dies then all its child thread will also terminates. – Grijesh Chauhan Dec 07 '12 at 12:15
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@KioMarv : CAUTION : All my answer is in context of C and by-default behaviour of thread..In python and Java there is concept of Demon thread also those are eligible to be alive even after main thread dies. There is a important role of virtual machine in thread execution. – Grijesh Chauhan Dec 07 '12 at 12:46
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You can learn more about thread termination issues [HERE](http://stackoverflow.com/questions/1725429/thread-termination-issue-c-programming) – Grijesh Chauhan Dec 07 '12 at 12:48
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1Don't worry!. I'm interested in C++ only. ust forgot to set that tag :D And thanks for the link!. – Kio Marv Dec 07 '12 at 13:05