unix网络编程（1）---客户端-服务器第一版

 1 #include <unistd.h>
 2 #include <stdlib.h>
 3 #include <errno.h>
 4 
 5 #define MAXLINE 1024
 6 
 7 extern int errno;
 8 
 9 void str_echo(int);
10 
11 int main() {
12     int sockfd;
13     sockfd = socket(AF_INET, SOCK_STREAM, 0);
14 
15     struct sockaddr_in servaddr, cliaddr;
16     bzero(&servaddr, sizeof(servaddr));
17     servaddr.sin_family = AF_INET;
18     servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
19     servaddr.sin_port = htons(7070);
20     bind(sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr));
21     listen(sockfd, 1024);
22 
23     for (;;) {
24         int connfd, childPid;
25         socklen_t len = sizeof(cliaddr);
26         connfd = accept(sockfd, (struct sockaddr *)&cliaddr, &len);
27 
28         if ((childPid = fork()) == 0) {
29             close(sockfd);
30             printf("connected with client.\n");
31             str_echo(connfd);
32             exit(0);
33         }
34     }
35 
36     printf("server end!\n");
37     return 0;
38 }
39 
40 void str_echo(int sockfd) {
41     ssize_t n;
42     char buf[MAXLINE];
43 
44 again:
45 
46     while ((n = read(sockfd, buf, MAXLINE)) > 0) {
47         printf("n:%ld\n", n);
48         write(sockfd, buf, n);
49         bzero(buf, MAXLINE);
50 
51         if (n < 0 && errno == EINTR) {
52             goto again;
53         } else if (n < 0) {
54             printf("str_echo:read error\n");
55         }
56     }
57 }

 1 #include <sys/socket.h>
 2 #include <netinet/in.h>
 3 #include <stdio.h>
 4 #include <string.h>
 5 #include <arpa/inet.h>
 6 #include <unistd.h>
 7 #include <unistd.h>
 8 
 9 #define MAXLINE 1024
10 
11 void str_cli(FILE *, int);
12 
13 int main() {
14     int sockfd;
15     const char *ip = "127.0.0.1";
16     in_port_t port = 7070;
17 
18     int i = 0;
19     sockfd = socket(AF_INET, SOCK_STREAM, 0);
20     struct sockaddr_in cliaddr;
21     bzero(&cliaddr, sizeof(cliaddr));
22     cliaddr.sin_family = AF_INET;
23     inet_aton(ip, &cliaddr.sin_addr);
24     cliaddr.sin_port = htons(port);
25 
26     int ret = connect(sockfd, (struct sockaddr *)&cliaddr, sizeof(cliaddr));
27     str_cli(stdin, sockfd);
28 
29     return 0;
30 }
31 
32 void str_cli(FILE *fp, int sockfd) {
33     char sendline[MAXLINE], recvline[MAXLINE];
34 
35     while (fgets(sendline, MAXLINE, fp) != NULL) {
36         write(sockfd, sendline, strlen(sendline));
37 
38         if (read(sockfd, recvline, MAXLINE) == 0) {
39             printf("server terminated prematurely\n");
40         }
41         fputs(recvline, stdout);
42         bzero(recvline, MAXLINE);
43     }
44 }