I want to use redis pubsub to transmit some messages, but don’t want be blocked using listen, like the code below:

while (true)
{
    if (redisGetReply(c, (void **)&reply) == REDIS_OK)
    {
        // do somethings 
        .
        .
        // do somethings 
    }

    // do somethings 
}

will be blocked waiting for a message. I want to check if there is a message then do somethings if no message go to next line.
how can I accomplish this?