[000]socket通信--server和client实现的简单例子

 1 #include<stdio.h>
 2 #include<stdlib.h>
 3 #include<string.h>
 4 #include<unistd.h>
 5 #include<arpa/inet.h>
 6 #include<sys/socket.h>
 7 
 8 void error_handling(char* message);
 9 
10 void error_handling(char* message) {
11     fputs(message, stderr);
12     fputc(‘\n‘, stderr);
13     exit(1);
14 }
15 
16 int main(int argc, char **argv)
17 {
18     int serv_sock;
19      int clnt_sock;
20    
21     //设置一个server地址serv_addr,client地址clnt_addr
22     struct sockaddr_in serv_addr;
23     struct sockaddr_in clnt_addr;
24     socklen_t clnt_addr_size = sizeof(clnt_addr);
25 
26     memset(&serv_addr, 0, sizeof(serv_addr));
27     memset(&serv_addr, 0, sizeof(serv_addr));
28     char message[] = "Hello world";
29 
30     if (argc != 2) {
31         printf("Usage : %s <port>\n", argv[0]);
32         exit(1);
33     }
34 
35     //创建用于internet的流协议(TCP)socket
36     serv_sock = socket(PF_INET, SOCK_STREAM, 0);
37     if (serv_sock == -1) {
38         error_handling("socket() error");
39     }
40  
41     serv_addr.sin_family = AF_INET;
42     serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
43     serv_addr.sin_port = htons(atoi(argv[1]));
44 
45     //把socket和socket地址结构联系起来
46     if( bind(serv_sock,(struct sockaddr*)&serv_addr,sizeof(serv_addr)) == -1) {
47         error_handling("bind() error");
48     }
49 
50     //server_socket用于监听
51     if ( listen(serv_sock, 5) == -1) {
52         error_handling("lisen() error");
53     }
54 
55     // 受理连接请求
56     clnt_sock = accept(serv_sock,(struct sockaddr*)&clnt_addr,&clnt_addr_size);
57     if ( clnt_sock == -1) {
58         error_handling("accept() error");
59     }
60 
61     write(clnt_sock, message, sizeof(message));
62     close(clnt_sock);
63     close(serv_sock);
64 
65     return 0;
66 }

 1 hello_client.c
 2 ------
 3 #include<stdio.h>
 4 #include<stdlib.h>
 5 #include<string.h>
 6 #include<unistd.h>
 7 #include<arpa/inet.h>
 8 #include<sys/socket.h>
 9 
10 void error_handling(char* message);
11 
12 void error_handling(char* message) {
13     fputs(message, stderr);
14     fputc(‘\n‘, stderr);
15     exit(1);
16 }
17 
18 int main(int argc, char **argv) {
19     int sock;
20     struct sockaddr_in serv_addr;
21     char message[30];
22     int str_len;
23     memset(&serv_addr, 0, sizeof(serv_addr));
24 
25     if (argc != 3)
26     {
27         printf("Usage: /%s <IP> <Port>\n",argv[0]);
28         exit(1);
29     }
30 
31     //创建用于internet的流协议(TCP)socket
32     sock = socket(PF_INET, SOCK_STREAM, 0);
33     if (sock == -1) {
34         error_handling("socket() error");
35     }
36 
37     //设置一个socket地址结构client_addr,代表客户机internet地址, 端口
38     serv_addr.sin_family = AF_INET;
39     serv_addr.sin_addr.s_addr = inet_addr(argv[1]);
40     serv_addr.sin_port = htons(atoi(argv[2]));
41 
42     //把socket和socket地址结构联系起来
43     if( connect(sock,(struct sockaddr*)&serv_addr,sizeof(serv_addr)) == -1) {
44         error_handling("connect() error");
45     }
46 
47     str_len = read(sock, message, sizeof(message) - 1);
48     if (str_len == -1) {
49         error_handling("read() error");
50     }
51 
52     printf("Message from server : %s \n", message);
53     close(sock);
54     return 0;
55 }

#gcc hello_server.c -o hserver 
#./hserver 9010
......开始挂起

#gcc hello_client.c -o hclient 
#./hclient 127.0.0.1 9010
Message from server: Hello world