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| ! <code>tcp-howto.c</code> | | ! <code>tcp-howto.c</code> |
| |- | | |- |
− | | <syntaxhighlight lang="c"> | + | | {{:Simple_TCP_pair/tcp-howto.c}} |
− | #include <sys/socket.h>
| |
− | #include <linux/types.h>
| |
− | #include <sys/types.h>
| |
− | #include <arpa/inet.h>
| |
− | #include <unistd.h>
| |
− | #include <string.h>
| |
− | #include <stdlib.h>
| |
− | #include <stdio.h>
| |
− | #include <signal.h>
| |
− | | |
− | static int serve_new_conn(int sk)
| |
− | { | |
− | int rd, wr;
| |
− | char buf[1024];
| |
− | | |
− | printf("New connection\n");
| |
− | | |
− | while (1) {
| |
− | rd = read(sk, buf, sizeof(buf));
| |
− | if (!rd)
| |
− | break;
| |
− | | |
− | if (rd < 0) {
| |
− | perror("Can't read socket");
| |
− | return 1;
| |
− | }
| |
− | | |
− | wr = 0;
| |
− | while (wr < rd) {
| |
− | int w;
| |
− | | |
− | w = write(sk, buf + wr, rd - wr);
| |
− | if (w <= 0) {
| |
− | perror("Can't write socket");
| |
− | return 1;
| |
− | }
| |
− | | |
− | wr += w;
| |
− | }
| |
− | }
| |
− | | |
− | printf("Done\n");
| |
− | return 0;
| |
− | }
| |
− | | |
− | static int main_srv(int argc, char **argv)
| |
− | {
| |
− | int sk, port, ret;
| |
− | struct sockaddr_in addr;
| |
− | | |
− | /*
| |
− | * Let kids die themselves
| |
− | */
| |
− | | |
− | signal(SIGCHLD, SIG_IGN);
| |
− | | |
− | sk = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
| |
− | if (sk < 0) {
| |
− | perror("Can't create socket");
| |
− | return -1;
| |
− | }
| |
− | | |
− | port = atoi(argv[1]);
| |
− | memset(&addr, 0, sizeof(addr));
| |
− | addr.sin_family = AF_INET;
| |
− | addr.sin_addr.s_addr = htonl(INADDR_ANY);
| |
− | addr.sin_port = htons(port);
| |
− | | |
− | printf("Binding to port %d\n", port);
| |
− | | |
− | ret = bind(sk, (struct sockaddr *)&addr, sizeof(addr));
| |
− | if (ret < 0) {
| |
− | perror("Can't bind socket");
| |
− | return -1;
| |
− | }
| |
− | | |
− | ret = listen(sk, 16);
| |
− | if (ret < 0) {
| |
− | perror("Can't put sock to listen");
| |
− | return -1;
| |
− | }
| |
− | | |
− | printf("Waiting for connections\n");
| |
− | while (1) {
| |
− | int ask, pid;
| |
− | | |
− | ask = accept(sk, NULL, NULL);
| |
− | if (ask < 0) {
| |
− | perror("Can't accept new conn");
| |
− | return -1;
| |
− | }
| |
− | | |
− | pid = fork();
| |
− | if (pid < 0) {
| |
− | perror("Can't fork");
| |
− | return -1;
| |
− | }
| |
− | | |
− | if (pid > 0)
| |
− | close(ask);
| |
− | else {
| |
− | close(sk);
| |
− | ret = serve_new_conn(ask);
| |
− | exit(ret);
| |
− | }
| |
− | }
| |
− | }
| |
− | | |
− | static int main_cl(int argc, char **argv)
| |
− | {
| |
− | int sk, port, ret, val = 1, rval;
| |
− | struct sockaddr_in addr;
| |
− | | |
− | sk = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
| |
− | if (sk < 0) {
| |
− | perror("Can't create socket");
| |
− | return -1;
| |
− | }
| |
− | | |
− | port = atoi(argv[2]);
| |
− | printf("Connecting to %s:%d\n", argv[1], port);
| |
− | memset(&addr, 0, sizeof(addr));
| |
− | addr.sin_family = AF_INET;
| |
− | ret = inet_aton(argv[1], &addr.sin_addr);
| |
− | if (ret < 0) {
| |
− | perror("Can't convert addr");
| |
− | return -1;
| |
− | }
| |
− | addr.sin_port = htons(port);
| |
− | | |
− | ret = connect(sk, (struct sockaddr *)&addr, sizeof(addr));
| |
− | if (ret < 0) {
| |
− | perror("Can't connect");
| |
− | return -1;
| |
− | }
| |
− | | |
− | while (1) {
| |
− | write(sk, &val, sizeof(val));
| |
− | rval = -1;
| |
− | read(sk, &rval, sizeof(rval));
| |
− | printf("PP %d -> %d\n", val, rval);
| |
− | sleep(2);
| |
− | val++;
| |
− | }
| |
− | }
| |
− | | |
− | int main(int argc, char **argv)
| |
− | {
| |
− | if (argc == 2)
| |
− | return main_srv(argc, argv);
| |
− | else if (argc == 3)
| |
− | return main_cl(argc, argv);
| |
− | | |
− | printf("Bad usage\n");
| |
− | return 1;
| |
− | }
| |
− | </syntaxhighlight>
| |
| |} | | |} |
| | | |