_tcp_file_svr.c

linux下的多个网络通讯的例子 可多参考下

/* TCP 文件服务器 演示代码 */
#include <stdio.h>                                       
#include <stdlib.h>                                      
#include <errno.h>                                       
#include <string.h>                                      
#include <sys/types.h>    
#include <sys/fcntl.h>   
#include <netinet/in.h>                                  
#include <sys/socket.h>                                  
#include <sys/wait.h>  

#include <pthread.h>
	
#define DEFAULT_SVR_PORT 2828	
	
	
#define FILE_MAX_LEN 64


char filename[FILE_MAX_LEN+1];

static void * handle_client(void * arg)
{
	FILE * file = NULL;
	int sock = (int)arg;
	char buff[1024];
	int len ;
	
	printf("begin send\n");
		
	file = fopen(filename,"r");
	if(!file)
		{
			close(sock);
			exit;
		}
		
	 if(send(sock,filename,FILE_MAX_LEN,0)== -1)
	 	{
	 		perror("send file name\n");
	 		goto EXIT_THREAD;
	 	}
	 
	 printf("begin send file %s....\n",filename);
	 	

	 	while(1)
	 	{
	 		len =fread(buff,1,sizeof(buff),file);
	 		if(len<= 0)
	 			break;
	 		printf("server read %s,len %d\n",filename,len);
	 		
	 		if(send(sock,buff,len,0)< 0)
	 			{
	 				 perror("send file:");
	 				 goto EXIT_THREAD;
	 			}
	 		
	 	}
	 	
EXIT_THREAD:
	if(file)	 	
	 fclose(file);
	 
	 close(sock);
	
}



 	
main(int argc,char * argv[]) {       
	                                          
		int sockfd,new_fd;                                       
		//第1.定义两个ipv4 地址,
		struct sockaddr_in my_addr;                              
		struct sockaddr_in their_addr;                           
		int sin_size,numbytes;    
		pthread_t cli_thread;
		
		unsigned short port;
	
		
		
		if(argc <2)
			{
				 printf("need a filename without path\n");
				 exit;
			}
			
			strncpy(filename,argv[1],FILE_MAX_LEN);
		
		 port = DEFAULT_SVR_PORT;
		 
		  if(argc >=3)
		  {
		  	 port = (unsigned short)atoi(argv[2]);
		  }
		                                      
		//第一步:建立TCP套接字 Socket  
		//         AF_INET --> ip通讯
		//				 SOCK_STREAM -->TCP                             
		if((sockfd = socket(AF_INET,SOCK_STREAM,0))==-1) {       
			perror("socket");                                        
			exit(1);                                                 
		}    
		
		//第二步:设置侦听端口                                                    
		//初始化结构体，并绑定2323端口 
		
		memset(&my_addr,0,sizeof(struct sockaddr_in)); 
		//memset(&my_addr,0,sizeof(my_addr)); 
		                         
		my_addr.sin_family = AF_INET;     /* ipv4 */                        
		my_addr.sin_port = htons(port);   /* 设置侦听端口是 2323 , 用htons转成网络序*/                       
		my_addr.sin_addr.s_addr = INADDR_ANY;    /* INADDR_ANY来表示任意IP地址可能其通讯 */                 
		//bzero(&(my_addr.sin_zero),8);                            
		
		//第三步:绑定套接口,把socket队列与端口关联起来.                                             
		if(bind(sockfd,(struct sockaddr *)&my_addr,sizeof(struct	sockaddr))==-1)                                          
		{                                                        
			perror("bind");                                          
			goto EXIT_MAIN;                                                  
		}                                                        
		//第四步:开始在2323端口侦听,是否有客户端发来联接                                         
		if(listen(sockfd,10)==-1) {                              
			perror("listen");                                        
			goto EXIT_MAIN;                                                  
		}                            
		
		printf("#@ listen port %d\n",port);
		//第五步:循环与客户端通讯                                               
		while(1) {                                               
			sin_size = sizeof(struct sockaddr_in); 
			                  
			printf("server waiting...\n");          
			                       
			//如果有客户端建立连接，将产生一个全新的套接字 new_fd,专门用于跟这个客户端通读                  
			if((new_fd = accept(sockfd,(struct sockaddr *)&their_addr,&sin_size))==-1)                             
			{                                                        
					perror("accept:");                                        
					goto EXIT_MAIN;                                                
			}             
			
			
			printf("---client (ip=%s:port=%d) request \n",inet_ntoa(their_addr.sin_addr),ntohs(their_addr.sin_port));
			//生成一个线程来完成和客户端的会话，父进程继续监听     
			 pthread_create(&cli_thread,NULL,handle_client,(void *)new_fd);
			
		}	
		//第六步:关闭socket    
EXIT_MAIN:		
		close(sockfd);                                           
}