try_lock

VALUE
rb_mutex_trylock(VALUE self)
{
    mutex_t *mutex;
    VALUE locked = Qfalse;
    GetMutexPtr(self, mutex);

    native_mutex_lock(&mutex->lock);
    if (mutex->th == 0) {
        mutex->th = GET_THREAD();
        locked = Qtrue;

        mutex_locked(GET_THREAD(), self);
    }
    native_mutex_unlock(&mutex->lock);

    return locked;
}