Method rdlock

src/bthread/rwlock.h:51–57

    native_handler_type native_handler() { return &_rwlock; }

    void rdlock() {
        int rc = bthread_rwlock_rdlock(&_rwlock);
        if (rc) {
            throw std::system_error(std::error_code(rc, std::system_category()),
                                    "RWLock rdlock failed");
        }
    }

    bool try_rdlock() {
        return 0 == bthread_rwlock_tryrdlock(&_rwlock);