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POaccept/epoll problem
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copied!<p>I have this code that uses epoll and it has a problem. When I run it, it gives output: Server-socket() is OK... Server-bind() is OK... 3 4 accept: Invalid argument</p> <p>I'm running it on ubuntu linux, system updated, both as limited user and root what is wrong with the input to accept? What should I change?</p> <pre><code> struct epoll_event ev, events[MAX_EVENTS]; struct sockaddr_in serveraddr; int listen_sock, conn_sock, nfds, epollfd; int yes = 1; /* Set up listening socket, 'listen_sock' (socket(), bind(), listen()) */ if((listen_sock = socket(AF_INET, SOCK_STREAM, 0)) == -1) { perror("Server-socket() error lol!"); //just exit lol! exit(1); } printf("Server-socket() is OK...\n"); //"address already in use" error message /*if(setsockopt(listen_sock, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int)) == -1) { perror("Server-setsockopt() error lol!"); exit(1); } printf("Server-setsockopt() is OK...\n");*/ // bind serveraddr.sin_family = AF_INET; serveraddr.sin_addr.s_addr = INADDR_ANY; serveraddr.sin_port = htons(PORT); memset(&(serveraddr.sin_zero), '\0', 8); if(bind(listen_sock, (struct sockaddr *)&serveraddr, sizeof(serveraddr)) == -1) { perror("Server-bind() error lol!"); exit(1); } printf("Server-bind() is OK...\n"); epollfd = epoll_create(MAX_EVENTS); if (epollfd == -1) { perror("epoll_create"); exit(EXIT_FAILURE); } ev.events = EPOLLIN; ev.data.fd = listen_sock; if (epoll_ctl(epollfd, EPOLL_CTL_ADD, listen_sock, &ev) == -1) { perror("epoll_ctl: listen_sock"); exit(EXIT_FAILURE); } for (;;) { nfds = epoll_wait(epollfd, events, MAX_EVENTS, -1); if (nfds == -1) { perror("epoll_pwait"); exit(EXIT_FAILURE); } for (int n = 0; n < nfds; ++n) { if (events[n].data.fd == listen_sock) { struct sockaddr_in clientaddr; socklen_t addrlen = sizeof(clientaddr); cout <<listen_sock <<'\n' <<epollfd <<'\n'; conn_sock = accept(listen_sock, (struct sockaddr *) &clientaddr, &addrlen); if (conn_sock == -1) { perror("accept"); exit(EXIT_FAILURE); } fcntl(conn_sock, F_SETFL, fcntl(conn_sock, F_GETFD, 0)|O_NONBLOCK); ev.events = EPOLLIN | EPOLLET; ev.data.fd = conn_sock; if (epoll_ctl(epollfd, EPOLL_CTL_ADD, conn_sock, &ev) == -1) { perror("epoll_ctl: conn_sock"); exit(EXIT_FAILURE); } } else { printf("%d\n", events[n].data.fd); } } } </code></pre>

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