linux下的UDP套接字编程

232131 · 发表于 2016-5-25 09:13:25

一.相关过程以及知识请详见我的另一篇博客《winsock套接字编程》，这里不再累述。

二.相关代码：
server.c：

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1 /****************************************
  2    > File Name:server.c
  3    > Author:xiaoxiaohui
  4    > mail:1924224891@qq.com
  5    > Created Time:2016年05月21日星期六 15时05分23秒
  6 ****************************************/
  7
  8 #include<stdio.h>
  9 #include<stdlib.h>
10 #include<sys/types.h>
11 #include<sys/socket.h>
12 #include<unistd.h>
13 #include<arpa/inet.h>
14 #include<netinet/in.h>
15 #include<string.h>
16
17 const int PORT = 9090;
18 const int LEN = 1024;
19 int serverSock;
20 struct sockaddr_in local;
21 struct sockaddr_in client;
22
23
24 int main()
25 {
26    serverSock = socket(AF_INET, SOCK_DGRAM, 0);
27
28    local.sin_family = AF_INET;
29    //local.sin_addr.s_addr = htonl(INADDR_ANY);
30    local.sin_port = htons(PORT);
31    local.sin_addr.s_addr = inet_addr("127.0.0.1");
32    bind(serverSock, (struct sockaddr*)&local, sizeof(local));
33
34    char buf[LEN];
35    while(1)
36    {
37       int ret = 0;
38       socklen_t  len = sizeof(client);
39       memset(buf, '\0', LEN);
40       ret = recvfrom(serverSock, buf, LEN - 1, 0, (struct sockaddr*)&client, &len);
41
42       printf("ret is %d", ret);
43       if(ret == 0)
44       {
45          printf("client is closed!\n");
46          exit(2);
47       }
48       else if(ret < 0)
49       {
50          perror("recvfrom");
51          continue;
52       }
53       else
54       {
55          buf[ret] = '\0';
56          printf("client[ip:%s][port:%d]# %s\n", inet_ntoa(client.sin_addr), \
57                   ntohs(client.sin_port), buf);
58          fflush(stdout);
59       }
60
61       if(strstr(buf, "quit") != NULL)
62       {
63          close(serverSock);
64          return 0;
65       }
66    }
67    return 0;
68 }

client.c：

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1 /****************************************
  2    > File Name:client.c
  3    > Author:xiaoxiaohui
  4    > mail:1924224891@qq.com
  5    > Created Time:2016年05月21日星期六 15时35分32秒
  6 ****************************************/
  7
  8 #include<stdio.h>
  9 #include<sys/types.h>
10 #include<sys/socket.h>
11 #include<unistd.h>
12 #include<arpa/inet.h>
13 #include<netinet/in.h>
14 #include<string.h>
15
16 const int PORT = 9090;
17 const char* IP = "127.0.0.1";
18 //const char* IP = "192.168.0.145";
19 const int LEN = 1024;
20 int clientSock;
21 struct sockaddr_in server;
22
23 int main()
24 {
25
26    clientSock = socket(AF_INET, SOCK_DGRAM, 0);
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28    server.sin_family = AF_INET;
29    server.sin_addr.s_addr = inet_addr(IP);
30    server.sin_port = htons(PORT);
31
32    char buf[LEN];
33    while(1)
34    {
35       memset(buf, '\0', LEN);
36       printf("please input: ");
37       fflush(stdout);
38       gets(buf);
39
40       int ret = sendto(clientSock, buf, strlen(buf), 0, (struct sockaddr*)&server, sizeof(server));
41       if(ret <= 0)
42       {
43          perror("sendto");
44          continue;
45       }
46
47       if(strcmp(buf, "quit") == 0)
48       {
49          close(clientSock);
50          return 0;
51       }
52    }
53
54    return 0;
55 }

Makefile：

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1 .PHONY:all
  2 all:server client
  3
  4 server:server.c
  5    gcc -o $@ $^ -g
  6 client:client.c
  7    gcc -o $@ $^ -g
  8
  9 .PHONY:clean
10 clean:
11    rm -f server client

执行结果：