Server.c

  1 #include <sys/types.h>
  2 #include <sys/socket.h>
  3 #include <netinet/in.h>
  4 #include <arpa/inet.h>
  5 #include <netdb.h>
  6 #include <stdio.h>
  7 #include <errno.h>
  8 #include <stdlib.h>
  9 #include <string.h>
 10 #include <unistd.h>
 11
 
 /************************************************************************************************************************
 12 1、int socket(int family,int type,int protocol)
 13 family:
 14     指定使用的協議簇:AF_INET（IPv4） AF_INET6（IPv6） AF_LOCAL（UNIX協議） AF_ROUTE（路由套接字） AF_KEY（秘鑰套接字）
 15 type:
 16     指定使用的套接字的類型:SOCK_STREAM（字節流套接字） SOCK_DGRAM
 
 17 protocol:
 18     如果套接字類型不是原始套接字，那麽這個參數就為0
 19 2、int bind(int sockfd, struct sockaddr *myaddr, int addrlen)
 20 sockfd:
 21     socket函數返回的套接字描述符
 22 myaddr:
 23     是指向本地IP地址的結構體指針
 24 myaddrlen:
 25     結構長度
 26 struct sockaddr{
 27     unsigned short sa_family; //通信協議類型族AF_xx
 28     char sa_data[14];  //14字節協議地址，包含該socket的IP地址和端口號
 
 29 };
 30 struct sockaddr_in{
 31     short int sin_family; //通信協議類型族
 32     unsigned short int sin_port; //端口號
 33     struct in_addr sin_addr; //IP地址
 34     unsigned char si_zero[8];  //填充0以保持與sockaddr結構的長度相同
 35 };
 36 3、int connect(int sockfd,const struct sockaddr *serv_addr,socklen_t addrlen)
 37 sockfd:
 38     socket函數返回套接字描述符
 39 serv_addr:
 40     服務器IP地址結構指針
 41 addrlen:
 42     結構體指針的長度
 43 4、int listen(int sockfd, int backlog)
 44 sockfd:
 45     socket函數綁定bind後套接字描述符
 46 backlog:
 47     設置可連接客戶端的最大連接個數，當有多個客戶端向服務器請求時，收到此值的影響。默認值20
 48 5、int accept(int sockfd,struct sockaddr *cliaddr,socklen_t *addrlen)
 49 sockfd:
 50     socket函數經過listen後套接字描述符
 51 cliaddr:
 52     客戶端套接字接口地址結構
 53 addrlen:
 54     客戶端地址結構長度
 55 6、int send(int sockfd, const void *msg,int len,int flags)
 56 7、int recv(int sockfd, void *buf,int len,unsigned int flags)
 57 sockfd:
 58     socket函數的套接字描述符
 59 msg:
 60     發送數據的指針
 61 buf:
 62     存放接收數據的緩沖區
 63 len:
 64     數據的長度，把flags設置為0
 65 *************************************************************************************************************************/
 66 int main(int argc, char *argv[])
 67 {
 68     int fd, new_fd, struct_len, numbytes,i;
 69     struct sockaddr_in server_addr;
 70     struct sockaddr_in client_addr;
 71     char buff[BUFSIZ];
 72 
 73     server_addr.sin_family = AF_INET;
 74     server_addr.sin_port = htons(8000);
 75     server_addr.sin_addr.s_addr = INADDR_ANY;
 76     bzero(&(server_addr.sin_zero), 8);
 77     struct_len = sizeof(struct sockaddr_in);
 78 
 79     fd = socket(AF_INET, SOCK_STREAM, 0);
 80     while(bind(fd, (struct sockaddr *)&server_addr, struct_len) == -1);
 81     printf("Bind Success!\n");
 82     while(listen(fd, 10) == -1);
 83     printf("Listening....\n");
 84     printf("Ready for Accept,Waitting...\n");
 85     new_fd = accept(fd, (struct sockaddr *)&client_addr, &struct_len);
 86     printf("Get the Client.");
 87     numbytes = send(new_fd,"Welcome to my server\n",21,0); 
 88     while((numbytes = recv(new_fd, buff, BUFSIZ, 0)) > 0)
 89     {
 90         buff[numbytes] = ‘\0‘;
 91         printf("%s\n",buff);
 92             if(send(new_fd,buff,numbytes,0)<0)  
 93             {  
 94                 perror("write");  
 95                 return 1;  
 96             }  
 97     }
 98     close(new_fd);
 99     close(fd);
100     return 0;
101 }

Client.c

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <netdb.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <arpa/inet.h>

int main(int argc,char *argv[])
{
    int sockfd,numbytes;
    char buf[BUFSIZ];
    struct sockaddr_in their_addr;
    printf("break!");
    while((sockfd = socket(AF_INET,SOCK_STREAM,0)) == -1);
    printf("We get the sockfd~\n");
    their_addr.sin_family = AF_INET;
    their_addr.sin_port = htons(8000);
    their_addr.sin_addr.s_addr=inet_addr("127.0.0.1");
    bzero(&(their_addr.sin_zero), 8);
    
    while(connect(sockfd,(struct sockaddr*)&their_addr,sizeof(struct sockaddr)) == -1);
    printf("Get the Server~Cheers!\n");
    numbytes = recv(sockfd, buf, BUFSIZ,0);//接收服務器端信息  
    buf[numbytes]=‘\0‘;  
    printf("%s",buf);
    while(1)
    {
        printf("Entersome thing:");
        scanf("%s",buf);
        numbytes = send(sockfd, buf, strlen(buf), 0);
            numbytes=recv(sockfd,buf,BUFSIZ,0);  
        buf[numbytes]=‘\0‘; 
        printf("received:%s\n",buf);  
    }
    close(sockfd);
    return 0;
}

未完待續~

Linux下C語言的socket網絡編程