I found this example; here the two threads threadDefault and threadCustomized are terminated by using pthread_exit followed by return. Why did the author write both instructions?
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You can check this: https://stackoverflow.com/questions/3844678/pthread-exit-vs-return – Ted Jun 30 '20 at 08:16
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Hello @Ted thank you for your suggestion. In the high score reply the OP used only pthread_exit. – Gennaro Arguzzi Jun 30 '20 at 08:21
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Mohith Reddy's answer is correct but misses the point. Of course the return statement is never executed since pthread_exit doesn't return, but it's there to suppress warnings from the compiler in case it's not aware that pthread_exit doesn't return.
R.. GitHub STOP HELPING ICE
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Yes that should be it! Even I am remembering now inserting a ``return`` myself after ``pthread_exit`` to suppress the compiler warnings. – m0hithreddy Jun 30 '20 at 11:46
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Thank you very much for your answer @R...GitHubSTOPHELPINGICE Could you do an example showing the warning you're talking about please? – Gennaro Arguzzi Jun 30 '20 at 15:12
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From the pthread_exit() man page:
RETURN VALUE
This function does not return to the caller.
ERRORS
This function always succeeds.
NOTES
Performing a return from the start function of any thread other than the main thread results in an implicit call to
pthread_exit(), using the function's return value as the thread's exit status.
The above all suggests that pthread_exit(); and return NULL; are redundant when both are called together.
m0hithreddy
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Hi @MohithReddy the strange thing is that, after the execution of the pthread_exit, the return should not be executed because the pthread_exit terminates the thread. – Gennaro Arguzzi Jun 30 '20 at 09:05
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@GennaroArguzzi Yes, that is how it should happen. Is ``return`` getting called after ``pthread_exit()``? If yes, how are you making sure? Sometimes IDE may not be following the source code well. – m0hithreddy Jun 30 '20 at 09:24