--- /dev/null
+#ifndef CONDITIONVARIABLE_H
+#define CONDITIONVARIABLE_H
+
+namespace std {
+ class mutex;
+
+ struct condition_variable_state {
+ int reserved;
+ };
+
+ class condition_variable {
+ public:
+ condition_variable();
+ ~condition_variable();
+ void notify_one();
+ void notify_all();
+ void wait(mutex& lock);
+
+ private:
+ struct condition_variable_state state;
+ };
+}
+#endif