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vector and threads

Posted on 2015-02-18
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Last Modified: 2015-02-18
Hi Experts,

I want to have a bunch of threads that share a vector.  If I keep a critical section around the vector at all places where it is accessed, am I ok?

i.e., I place a critical section around the size() call where the parent class that owns the vector is a GetSize

I place a critical section around code that adds items to the vector in the AddItem function

Is there anything else to watch out for?

Thanks,
Mike
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Question by:thready
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Author Comment

by:thready
ID: 40617226
Also, my concern is here:


int TaskRunner::GetNumberOfTasksInQueue()
{
      EnterCriticalSection(&m_QueueCriticalSection);

      int nSize = m_TaskQueue.size();

      LeaveCriticalSection(&m_QueueCriticalSection);

     // RIGHT HERE - SIZE MIGHT BE INCORRECT - ANOTHER THREAD MAY HAVE COME IN AND CHANGED SIZE
//  JUST BEFORE I GOT TO RETURN IT.  HOW DO I FIX THIS?

      return nSize;
}
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Author Comment

by:thready
ID: 40617232
ignore that last concern - I realized that size is a stack variable - not a member variable like I was thinking....
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Accepted Solution

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jkr earned 500 total points
ID: 40617318
>> If I keep a critical section around the vector at all places where it is accessed, am I ok?

Short ad sweet: if 'accessed' means both read and write access, you are absolutely fine.
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Author Closing Comment

by:thready
ID: 40617388
Gracias amigo
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