tcp_self_connection.cpp

int main(int argc, char *argv[])
{
    int sockfd = socket(AF_INET, SOCK_STREAM, 0); 
    if (sockfd < 0) {
        perror("new socket error");
        exit(-1);
    }   

    struct sockaddr_in servaddr;
    bzero(&servaddr, sizeof(servaddr));
    servaddr.sin_addr.s_addr = inet_addr("127.0.0.1");
    servaddr.sin_port = htons(42768);
    servaddr.sin_family = AF_INET;

    while (connect(sockfd, (sockaddr *)&servaddr, sizeof(servaddr)) == -1);

    printf("connected!\n");

    pause();
        
    return 0;
}