Method try_acquire

tests/BS_thread_pool_test.cpp:184–193

* @brief Tries to atomically decrement the internal counter by 1 if it is greater than 0; no blocking occurs regardless. * * @return `true` if decremented the internal counter, `false` otherwise. */

     * @return `true` if decremented the internal counter, `false` otherwise.
     */
    bool try_acquire()
    {
        std::scoped_lock lock(mutex);
        if (counter > 0)
        {
            --counter;
            return true;
        }
        return false;
    }

    /**
     * @brief Tries to atomically decrement the internal counter by 1 if it is greater than 0; otherwise blocks until it is greater than 0 and can successfully decrement the internal counter, or the `rel_time` duration has been exceeded.