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POboost thread deadlock, can anyone check why?
 

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  1. POboost thread deadlock, can anyone check why?
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    <p>I tried to write a program that can have mutiple-threaded reads and writes. It works fine with one read and one write, but it ended in deadlock when I use two reads and one write.</p> <p>Can anyone help to check?</p> <pre><code>const int BUF_SIZE = 10; const int ITERS = 100; boost::mutex io_mutex; class buffer { public: typedef boost::mutex::scoped_lock scoped_lock; buffer() : p(0), c(0), full(0) {} void put(int m) { scoped_lock lock(mutex); if (full == BUF_SIZE) { { boost::mutex::scoped_lock lock(io_mutex); std::cout &lt;&lt; "Buffer is full. Waiting..." &lt;&lt; std::endl; } while (full == BUF_SIZE) cond.wait(lock); } buf[p] = m; p = (p+1) % BUF_SIZE; ++full; cond.notify_all(); } int get() { scoped_lock lk(mutex); if (full == 0) { { boost::mutex::scoped_lock lock(io_mutex); std::cout &lt;&lt; "Buffer is empty. Waiting..." &lt;&lt; std::endl; } while (full == 0) cond.wait(lk); } int i = buf[c]; c = (c+1) % BUF_SIZE; --full; cond.notify_one(); return i; } private: boost::mutex mutex; boost::condition cond; unsigned int p, c, full; int buf[BUF_SIZE]; }; buffer buf; void writer() { for (int n = 0; n &lt; ITERS; ++n) { { boost::mutex::scoped_lock lock(io_mutex); std::cout &lt;&lt; "sending: " &lt;&lt; n &lt;&lt; std::endl; } buf.put(n); } } void reader() { for (int x = 0; x &lt; ITERS; ++x) { int n = buf.get(); { boost::mutex::scoped_lock lock(io_mutex); std::cout &lt;&lt; "reader1: received: " &lt;&lt; n &lt;&lt; std::endl; } } } int main(int argc, char* argv[]) { boost::thread thrd1(&amp;reader); boost::thread thrd2(&amp;writer); boost::thread thrd3(&amp;reader); std::string str; thrd1.join(); thrd2.join(); thrd3.join(); std::getline(std::cin,str); } </code></pre>
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    1. USMichael
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    1. COThe whitespace of doom!
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      1. USRichard J. Ross III
    2. COSorry, my stupid mistake, didn't write enough data for two readers.
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      1. USMichael
 

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