SOkit的C语言源程序

有用的sokit

1. #include<stdio.h>
   
2. #include<stdlib.h>
   
3. #include<errno.h>
   
4. #include<string.h>
   
5. #include<netdb.h>
   
6. #include<sys/types.h>
   
7. #include<netinet/in.h>
   
8. #include<sys/socket.h>
   
9. #define PORT 4321
   
10. #define BUF_SIZE 1024
    
11. int main(int argc, char *argv[])
    
12. {
    
13. int sockfd, sendbytes, recvbytes;
    
14. char buf[BUF_SIZE];
    
15. struct hostent *host;
    
16. struct sockaddr_in serv_addr;
    
17. if(argc<2)
    
18. {// 检查程序参数个
    
19. printf("USAGE: ./tclient Hostname(or ip address)\n");
    
20. exit(1);
    
21. }
    
22. //检查程序参数指定的服务器地止
    
23. if((host = gethostbyname(argv[1])) == NULL)
    
24. {
    
25. perror("gethostbyname");
    
26. exit(1);
    
27. }
    
28. if((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1)
    
29. {// 创建一个流
    
30. socket perror("socket");
    
31. exit(1);
    
32. }
    
33. //初始化serv_addr结构体变
    
34. serv_addr.sin_family = AF_INET;
    
35. serv_addr.sin_port=htons(PORT);
    
36. serv_addr.sin_addr=*((struct in_addr *)host->h_addr);
    
37. bzero(&(serv_addr.sin_zero), 8);
    
38. // 连接服务
    
39. if(connect(sockfd,(struct sockaddr *)&serv_addr,sizeof(struct sockaddr)) == -1)
    
40. {perror("connect");
    
41. exit(1);
    
42. }// 显示连接信
    
43. printf("connect to server %s...\nInput the msg to send:\n", argv[1]);
    
44. while (1)
    
45. { // 循环发送、接收服务器信
    
46. bzero(buf, sizeof(buf));// 清空缓
    
47. if(fgets(buf, BUF_SIZE, stdin)) {
    
48. // 终端输入一行数据
    
49. if (strcmp(buf, "exit\n") == 0) break;// 判断是否退出循
    
50. if ((sendbytes = send(sockfd, buf, strlen(buf), 0)) == -1)
    
51. { // 是否发送成功
    
52. perror("send");
    
53. exit(1);
    
54. }
    
55. }
    
56. bzero(buf, sizeof(buf));// 清空缓冲
    
57. if((recvbytes = recv(sockfd, buf, BUF_SIZE, 0)) == -1)
    
58. {
    
59. // 等待接收数据
    
60. perror("recv");
    
61. exit(1);
    
62. }
    
63. else printf("receive from %d(socket): %s\n", sockfd, buf); // 打印接收数据 }
    
64. close(sockfd);// 关闭
    
65. socket return 0;
    
66. }
    
67. 
    
68. 
    
69. #include<stdio.h>
    
70. #include<stdlib.h>
    
71. #include<unistd.h>
    
72. #include<sys/types.h>
    
73. #include<sys/stat.h>
    
74. #include<string.h>
    
75. #include<sys/socket.h>
    
76. #include<netinet/in.h>
    
77. #include<netdb.h>
    
78. #include<time.h>
    
79. #include <string.h>
    
80. #include <sys/ioctl.h>
    
81. #include <arpa/inet.h>
    
82. #define PORT 4321
    
83. #define MAX_QUE_CONN_NM 5
    
84. #define MAX_SOCK_FD FD_SETSIZE
    
85. #define BUFFER_SIZE 1024
    
86. #define HOSTLEN 256
    
87. int main()
    
88. {
    
89. struct sockaddr_in  server_sockaddr, client_sockaddr;
    
90. int sin_size, count;
    
91. fd_set inset, tmp_inset;
    
92. int sockfd, client_fd, fd;
    
93. char buf[BUFFER_SIZE];
    
94. // 接收、发送缓
    
95. struct sockaddr_in scinf[100];
    
96. // 客户端地址池
    
97. bzero((void *)scinf, sizeof(scinf));
    
98. // 创建
    
99. socket if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1)
    
100. {
     
101. perror("socket");
     
102. exit(1);
     
103. }
     
104. // 初始化服务器地址结构体
     
105. server_sockaddr.sin_family=AF_INET;
     
106. server_sockaddr.sin_port=htons(PORT);
     
107. server_sockaddr.sin_addr.s_addr = INADDR_ANY;
     
108. bzero(&(server_sockaddr.sin_zero), 8);
     
109. // 为bind设置地址复用
     
110. int i = 1;
     
111. setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &i, sizeof(i));
     
112. if(bind(sockfd, (struct sockaddr *)&server_sockaddr, sizeof(struct sockaddr))==-1)
     
113. {
     
114. perror("bind");
     
115. exit(1);
     
116. }
     
117. // 开始侦听客户端连
     
118. if(listen(sockfd, MAX_QUE_CONN_NM) == -1)
     
119. {
     
120. perror("listen");
     
121. exit(1);
     
122. }
     
123. printf("Begin listening...\n");
     
124. // 准备非阻塞方式连接多路客户端
     
125. FD_ZERO(&inset);
     
126. FD_SET(sockfd, &inset);
     
127. while (1)
     
128. {
     
129. tmp_inset = inset;
     
130. sin_size = sizeof(struct sockaddr_in);
     
131. memset(buf, 0, sizeof(buf));
     
132. if(!(select(MAX_SOCK_FD, &tmp_inset, NULL, NULL, NULL) > 0))
     
133. {//等待网络消息
     
134. perror("select");
     
135. exit(1);
     
136. }
     
137. for(fd = 0; fd < MAX_SOCK_FD; ++fd)
     
138. {
     
139. if (FD_ISSET(fd, &tmp_inset) > 0)
     
140. {
     
141. if (fd == sockfd)
     
142. {// 有客户端连接请求，accept
     
143. if((client_fd = accept(sockfd, (struct sockaddr*)&client_sockaddr, &sin_size))==-1)
     
144. {
     
145. perror("accept");
     
146. exit(1);
     
147. }
     
148. FD_SET(client_fd, &inset);
     
149. printf("New connection from %s\n", inet_ntoa(client_sockaddr.sin_addr));
     
150. if(client_fd < 100 && client_fd >= 0)// 新连接客户端记入地址
     
151. memcpy((void *)(&scinf[client_fd]), (void *)&client_sockaddr, sin_size);
     
152. }
     
153. ellse
     
154. {
     
155. // 有客户端数据
     
156. if((count = recv(fd, buf, BUFFER_SIZE, 0)) > 0)
     
157. {// 接收数
     
158. if(fd >= 0 && fd < 100)
     
159. printf("Received from %s:\t%s\n", inet_ntoa(scinf[fd].sin_addr), buf);
     
160. if((count = send(fd, buf, strlen(buf), 0)) == -1)
     
161. { // 回送数据
     
162. perror("send");
     
163. exit(1);
     
164. }
     
165. }
     
166. else
     
167. {// 无法读取数据，可能连接以断
     
168. if(fd >= 0 && fd < 100)
     
169. printf("Client %s has left\n", inet_ntoa(scinf[fd].sin_addr));
     
170. memset((void *)(&scinf[client_fd]), 0, sin_size);
     
171. close(fd);
     
172. FD_CLR(fd, &inset);
     
173. }
     
174. }
     
175. }
     
176. }
     
177. }
     
178. close(sockfd); return 0;
     
179. }
     

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