Linux最简单的网络通信

服务器端

/* socket server * 2014-12-15 CopyRight (c) arbboter */#include <unistd.h>#include <stdio.h>#include <stdlib.h>#include <time.h>#include <sys/socket.h>#include <sys/types.h>#include <netdb.h>#include <string.h>#include <arpa/inet.h>int main(){    int sockfd_server;    int sockfd_client;    struct sockaddr_in addr_server;    struct sockaddr_in addr_client;    socklen_t addr_len = 0;    int client_max = 10;    int server_port = 33892;    srand(time(NULL));        // create socket    sockfd_server = socket(AF_INET, SOCK_STREAM, 0);    if(sockfd_server == -1)    {        printf("init socket failed\n");        return -1;    }    // set address    memset(&addr_server, 0, sizeof(addr_server));    addr_server.sin_family = AF_INET;    addr_server.sin_addr.s_addr = htonl(INADDR_ANY);    addr_server.sin_port = htons(server_port);        // socket bind with address    if(bind(sockfd_server, (struct sockaddr*)&addr_server, sizeof(struct sockaddr)) == -1)    {        printf("bind socket failed\n");        return -1;    }    // server socket start list, waitting client to connect    // 这个client_max是指同时连接数    if(listen(sockfd_server, client_max) == -1)    {        printf("start listen socket failed\n");        return -1;    }    char szMsg[128] = {0};    while(1)    {        addr_len = sizeof(struct sockaddr_in);        printf("waitting for connected...\n");                // waitting for connected        sockfd_client = accept(sockfd_server, (struct sockaddr*)&addr_client, &addr_len);        if(sockfd_client == -1)        {            printf("accept socket failed\n");            return -1;        }                // get client ip and send a magic number to the client,         // then close this connection        printf("recived connection from : %s\n", inet_ntoa(addr_client.sin_addr));        sprintf(szMsg, "Your magic number is : %d", rand()%100);        write(sockfd_client, szMsg, strlen(szMsg));        close(sockfd_client);    }    close(sockfd_server);    return 0;}

客户端

/* socket client * 2014-12-15 CopyRight (c) arbboter */#include <unistd.h>#include <stdio.h>#include <stdlib.h>#include <sys/socket.h>#include <sys/types.h>#include <netdb.h>#include <string.h>#include <arpa/inet.h>int main(){    int sockfd_server;    struct sockaddr_in addr_server;    socklen_t addr_len = 0;    int server_port = 33891;    char* server_addr = "192.168.2.200";    // create socket    sockfd_server = socket(AF_INET, SOCK_STREAM, 0);    if(sockfd_server == -1)    {        printf("init socket failed\n");        return -1;    }        // set server address    memset(&addr_server, 0, sizeof(addr_server));    addr_server.sin_family = AF_INET;    addr_server.sin_addr.s_addr = inet_addr(server_addr);;    addr_server.sin_port = htons(server_port);        // connect server    if(connect(sockfd_server,(struct sockaddr *)&addr_server,sizeof(struct sockaddr))==-1)    {        printf("connect server failed\n");        return -1;    }        char szBuf[512] = {0};    int nRead = 0;        // recived data from server and print it    nRead = read(sockfd_server, szBuf, sizeof(szBuf));    printf("recived from server : %s\n", szBuf);            close(sockfd_server);    return 0;}

运行结果

# server output[arbboter@arser]$ g++ server.cpp -o server[arbboter@arser]$ ./serverwaitting for connected...recived connection from : 192.168.2.200waitting for connected...recived connection from : 192.168.2.200waitting for connected...recived connection from : 192.168.2.200waitting for connected...recived connection from : 192.168.2.200waitting for connected...# client output[arbboter@arser]$ g++ client.cpp -o client[arbboter@arser]$ ./clientrecived from server : Your magic number is : 5[arbboter@arser]$ ./clientrecived from server : Your magic number is : 43[arbboter@arser]$ ./clientrecived from server : Your magic number is : 88[arbboter@arser]$ ./clientrecived from server : Your magic number is : 28[arbboter@arser]$