Method acquire

gecode/support/thread/thread.cpp:113–121

        }
      }
      void acquire(Mutex* m) {
        _m_write.acquire();
        _m.acquire();
        _to_acquire = m;
        _m.release();
        _e.signal();
        _e_done.wait();
        _m_write.release();
      }
      void release(Mutex* m) {
        _m_write.acquire();
        _m.acquire();