//-----------------------Includes #include #include #include #include #include #include #include #include #include //----------------------- //-----------------------MISC #pragma comment(lib, "wsock32") using namespace std; //----------------------- #define MYPORT 8200 // the port users will be connecting to #define BACKLOG 10 // how many pending connections queue will hold #define MAXBUFLEN 100 void sigchld_handler(int s) { while(waitpid(-1, NULL, WNOHANG) > 0); } int main() { int sockfd, new_fd; // listen on sock_fd, new connection on new_fd struct sockaddr_in my_addr; // my address information struct sockaddr_in their_addr; // connector's address information socklen_t sin_size; struct sigaction sa; int yes=1; if ((sockfd = socket(PF_INET, SOCK_STREAM, 0)) == -1) { perror("socket"); exit(1); } if (setsockopt(sockfd,SOL_SOCKET,SO_REUSEADDR,&yes,sizeof(int)) == -1) { perror("setsockopt"); exit(1); } my_addr.sin_family = AF_INET; // host byte order my_addr.sin_port = htons(MYPORT); // short, network byte order my_addr.sin_addr.s_addr = INADDR_ANY; // automatically fill with my IP memset(my_addr.sin_zero, '\0', sizeof my_addr.sin_zero); if (bind(sockfd, (struct sockaddr *)&my_addr, sizeof(struct sockaddr))== -1) { perror("bind"); exit(1); } if (listen(sockfd, BACKLOG) == -1) { perror("listen"); exit(1); } sa.sa_handler = sigchld_handler; // reap all dead processes sigemptyset(&sa.sa_mask); sa.sa_flags = SA_RESTART; if (sigaction(SIGCHLD, &sa, NULL) == -1) { perror("sigaction"); exit(1); } while(1) { // main accept() loop sin_size = sizeof(struct sockaddr_in); if ((new_fd = accept(sockfd, (struct sockaddr *)&their_addr, &sin_size)) == -1) { perror("accept"); continue; } printf("server: got connection from %s\n", inet_ntoa(their_addr.sin_addr)); if (!fork()) { // this is the child process close(sockfd); // child doesn't need the listener if (send(new_fd, "Hello, world!\n", 14, 0) == -1) perror("send"); shutdown(new_fd, 2); exit(0); } shutdown(new_fd, 2); // parent doesn't need this } return 0; }