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WaitForSingleObject not returning, no timeout
Hello
I have a multithreaded application that uses semaphores to protect critical sections. The application seems to work fine, but I happens after running for several days that the thread is blocked for good. I assume it's the WaitForSingleObject call with timeout value 1000, i.e. 1 second, that never returns.
I've read about problems using WaitForSingleObject on hyperthreaded computers. Is it possible that no timeout happens and the thread is waiting for the signaled state for an infinite time?
Thanks for your help.
Martin
I have a multithreaded application that uses semaphores to protect critical sections. The application seems to work fine, but I happens after running for several days that the thread is blocked for good. I assume it's the WaitForSingleObject call with timeout value 1000, i.e. 1 second, that never returns.
I've read about problems using WaitForSingleObject on hyperthreaded computers. Is it possible that no timeout happens and the thread is waiting for the signaled state for an infinite time?
Thanks for your help.
Martin
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ASKER
This is how I'm calling WaitForSingleObject:
::WaitForSingleObject(m_hS
m_hSemaphore is a HANDLE to my semaphore.
::WaitForSingleObject(m_hS
m_hSemaphore is a HANDLE to my semaphore.
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ASKER
Thank you for your answers.
The semaphore is checked in a function:
return ( ::WaitForSingleObject(sema
This seems very dangerous to me, because the function is only returning true if a timeout happes, but returns false if signaled OR error. Maybe, this explains why the application is running a long time before hanging. An error gets treated like a signaled state.
I have corrected the return value handling and will run a test over night (it's 15:30 here). I will be back tomorrow with the results of that test. Thank you so far for your help.
The semaphore is checked in a function:
return ( ::WaitForSingleObject(sema
This seems very dangerous to me, because the function is only returning true if a timeout happes, but returns false if signaled OR error. Maybe, this explains why the application is running a long time before hanging. An error gets treated like a signaled state.
I have corrected the return value handling and will run a test over night (it's 15:30 here). I will be back tomorrow with the results of that test. Thank you so far for your help.
Good luck /w that . ...
In case if it fails again, you should attach a debuger to the running process and check the call stack of each thread, values of your variables etc. That should give you a better insight.
~j
ASKER
My test has been running for 22 hours now with no error. I hope that it's because of the changes regarding the return values. Past tests have shown an error after several days, so I'm still testing.
Please be patient, the test will continue over the weekend and I will reward points on monday.
So long,
Martin
Please be patient, the test will continue over the weekend and I will reward points on monday.
So long,
Martin
ASKER
Hi again,
the test has been running over the weekend without any problems. I guess it was the non-existing error handling that made the app crash. Thank you a lot for your great help.
Martin
the test has been running over the weekend without any problems. I guess it was the non-existing error handling that made the app crash. Thank you a lot for your great help.
Martin
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Can you show how you calling calling WaitForSingleObject?
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