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// std::lock example
#include <iostream> // std::cout
#include <thread> // std::thread
#include <mutex> // std::mutex, std::try_lock
std::mutex foo,bar;
void task_a () {
foo.lock();
std::cout << "task a\n";
bar.lock();
// ...
foo.unlock();
bar.unlock();
}
void task_b () {
int x = try_lock(bar,foo);
if (x==-1) {
std::cout << "task b\n";
// ...
bar.unlock();
foo.unlock();
}
else {
std::cout << "[task b failed: mutex " << (x?"foo":"bar") << " locked]\n";
}
}
int main ()
{
std::thread th1 (task_a);
std::thread th2 (task_b);
th1.join();
th2.join();
return 0;
}
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