客户端/服务器C连接

Question

I am currently doing a client / server application in C that words over the internet.The server is to keep listening for new connections from the clients. Currently I am listening to cllients, but once a client connects, the server wont keep on listening for further clients. The following depicts the server side code to connect with a client:

int sockfd = socket(AF_INET, SOCK_STREAM, 0);

struct sockaddr_in sockaddr, cliaddr;
bzero(&sockaddr, sizeof(struct sockaddr_in));
bzero(&cliaddr, sizeof(struct sockaddr_in));

    sockaddr.sin_family = AF_INET;
    sockaddr.sin_addr.s_addr = INADDR_ANY;
    sockaddr.sin_port = ntohs(atoi(argv[1]));

if(bind(sockfd, (struct sockaddr *) &sockaddr, sizeof(sockaddr)) <0) {
    printf("error binding socket: %d\n", errno);
    exit(1);
}

printf("binded to %d : %d\n", sockaddr.sin_addr.s_addr, htons(sockaddr.sin_port));

listen(sockfd,5);
socklen_t clilen = sizeof(cliaddr);
int newsockfd = accept(sockfd, (struct sockaddr *) &cliaddr, &clilen);
    if (newsockfd < 0) 
        error("ERROR on accept");

printf("server connected to %d:%d\n", cliaddr.sin_addr.s_addr, htons(cliaddr.sin_port));

I am assuming i have to create some form of threads that will fork once a connection has been established. But i dont know how to implement it..

Any help is greatly appreciated

Answer 1

Following points might help:

1. You should have your accept call in a loop, so that after accepting one connection, it can go back again to accept more connections.
2. To process each of the connections seperately, you can create threads using pthread_create or some similar thread creation APIs .
3. You can choose to use Non-Blocking sockets using which you can process multiple-connections in the same thread easily.

Answer 2

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