Create a CRITICAL_SECTION object cs and initialize it
with InitializeCriticalSection(&cs);
Then see code inserted in-line...
PaulH wrote:
I have a thread that listens on a message queue and populates a
std::deque with events from that message queue, but only holds the
latest 100.
In my main thread, I want to populate a listbox with the information
from that deque. So, it ends up being that one thread can add/remove
items from the deque while another thread is trying to iterate through
them. How can I make this thread-safe?
Thanks,
PaulH
The code looks a bit like this:
std::deque<MESSAGE_TYPE> m_dequeMessages;
CMyClass::MessageThread()
{
//...
while (ReadMsgQueue(hMsgQueue, &msg,...))
{
---> EnterCriticalSection(&cs);
m_dequeMessages.push_back(msg);
if(m_dequeMessages.size() > 100)
m_dequeMessages.pop_front();
---> LeaveCriticalSection(&cs);
}
//...
}
CListCtrl c_MyList;
CDlgClass::PopulateList()
{
---> EnterCriticalSection(&cs);
for (vector::iterator i = m_dequeMessages.begin(),
i != m_vMessages.end()
++i)
{
c_MyList.InsertItem(0, i->Message);
}
---> LeaveCriticalSection(&cs);
}
This will cause one thread to wait (at Enter...) if the other thread is
within the critical section.
--
Scott McPhillips [VC++ MVP]