Linux网络编程——Socket相关代码实战

客户端代码实现

相关函数如下

代码编程时也应按一下顺序：

（1）socket函数

int socket(int domain,int type, int protocol);

（2）connect函数

int connect (int sockfd, struct sockaddr *addr, socklen_t addrlen);

（3）write函数

ssize_t write(int fd,void *buf,size_t nbyte);

（4）raad函数

ssize_t read(int fd, const void *buf,size_t nbytes);

代码示例

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

int main()
{
	int c_fd;
	int n_read;
	char readBuf[128];	
	char *msg = "message from FuwuDuan";

	struct sockaddr_in c_addr;
	
    memset(&c_addr,0,sizeof(struct sockaddr_in));

	c_fd = socket(AF_INET,SOCK_STREAM,0);
	if(c_fd == -1)
	{
		perror("socket");
		exit(-1);
	}
	
	c_addr.sin_family = AF_INET;
	c_addr.sin_port = htons(8888);

 	inet_aton("127.0.0.1",&c_addr.sin_addr);
		
	if(connect(c_fd,(struct sockaddr *)&c_addr,sizeof(struct sockaddr)) == -1)
	{
		perror("connect");
		exit(-1);
	}

	write(c_fd,msg,strlen(msg));//先发送到服务端 服务端先read并将其打印
	
	n_read = read(c_fd,readBuf,128);
    if(n_read == -1)
    {
        perror("read");
    }
    else
    {
        printf("get message from FuwuDuan:%d,%s\n",n_read,readBuf);
    }
	
	return 0;
}

编译结果：服务端相关代码在上一章节中，客户端write相关信息给服务端，服务端先read并打印调试信息再write发送给客户端中的read，客户端再将read调试信息打印出来。

实现客户端与服务端间信息交流

服务端

相关函数入下

 （1）socket函数

int socket(int domain,int type, int protocol);

（2）bind函数

int bind(int sockfd, const struct sockaddr *addr,int addrlen);

（3）listen函数

int listen(SOCKET sockfd, int backlog);

（4）accept函数

int accept (int sockfd, struct sockaddr *addr, socklen_t *addrlen);	

（5）read函数

ssize_t read(int fd,void *buf,size_t nbyte);

（6）write函数

ssize_t write(int fd, const void *buf,size_t nbytes);

代码示例

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

int main(int argc,char **argv)
{
	int s_fd;
	int c_fd;
	int n_read;
	char readBuf[128];	
	char msg[128] ={0};

	struct sockaddr_in s_addr;
	struct sockaddr_in c_addr;
	
	memset(&s_addr,0,sizeof(struct sockaddr_in));
        memset(&c_addr,0,sizeof(struct sockaddr_in));

	if(argc != 3)
	{
		printf("param is not good\n");
		exit(-1);
	}

	s_fd = socket(AF_INET,SOCK_STREAM,0);
	if(s_fd == -1)
	{
		perror("socket");
		exit(-1);
	}
	
	s_addr.sin_family = AF_INET;
	s_addr.sin_port = htons(atoi(argv[2]));//将字符串转化为整型数

 	inet_aton(argv[1],&s_addr.sin_addr);
		
	bind(s_fd,(struct sockaddr *)&s_addr,sizeof(struct sockaddr_in));

	listen(s_fd,10);

	int clen = sizeof(struct sockaddr_in);
	while(1)
	{
		c_fd = accept(s_fd,(struct sockaddr *)&c_addr,&clen);
		if(c_fd == -1)
		{  
        	perror("accept");
			exit(-1);
        }
		printf("get connect :%s\n",inet_ntoa(c_addr.sin_addr));
		
		if(fork() == 0)/创建子进程
		{
			if(fork() == 0)
            {
			    while(1)
              	{
                    memset(msg,0,sizeof(msg));//清空数据
               		printf("input:");
                   	gets(msg);//scanf（）
                   	write(c_fd,msg,strlen(msg));
               	}
			}	
			while(1)
			{
				n_read = read(c_fd,readBuf,128);
        		if(n_read == -1)
        		{
               		perror("read");
        		}
        		else
        		{
                	printf("get message:%d,%s\n",n_read,readBuf);
        		}
			}
			break;	
		}
		
	}

	return 0;
}

客户端

相关函数如下

 （1）socket函数

int socket(int domain,int type, int protocol);

（2）connect函数

int connect (int sockfd, struct sockaddr *addr, socklen_t addrlen);

（3）write函数

ssize_t write(int fd,void *buf,size_t nbyte);

（4）raad函数

ssize_t read(int fd, const void *buf,size_t nbytes);

代码示例

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

int main(int argc,char **argv)
{
	int c_fd;
	int n_read;
	char readBuf[128];	
	char msg[128] = {0};

	struct sockaddr_in c_addr;
	
    memset(&c_addr,0,sizeof(struct sockaddr_in));

    if(argc != 3)
    {
        printf("parm is not good\n");
        exit(-1);
    }

	c_fd = socket(AF_INET,SOCK_STREAM,0);
	if(c_fd == -1)
	{
		perror("socket");
		exit(-1);
	}
	
	c_addr.sin_family = AF_INET;
	c_addr.sin_port = htons(atoi (argv[2]));

 	inet_aton(argv[1],&c_addr.sin_addr);
		
	if(connect(c_fd,(struct sockaddr *)&c_addr,sizeof(struct sockaddr)) == -1)
	{
		perror("connect");
		exit(-1);
	}

	while(1)
	{
		if(fork() == 0)
		{
			while(1)
			{
				memset(msg,0,sizeof(msg));
				printf("input: ");
				gets(msg);
				write(c_fd,msg,strlen(msg));
			}
		}
		while(1)
		{
			memset(msg,0,sizeof(msg));	
			n_read = read(c_fd,readBuf,128);
        		if(n_read == -1)
        		{
                    perror("read");
        		}
        		else
        		{
                    printf("get message from FuwuDuan:%d,%s\n",n_read,readBuf);
			}
		}
    }
	
	return 0;
}

代码现象

实现了服务端与客户端信息交流