client.c

在linux下创建了客户端和服务端（c/s）

/******* 客户端程序  (client.c) ************/
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <netdb.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <sys/types.h>
#include <arpa/inet.h>
#include <sys/stat.h>
#include <fcntl.h>

#define MAXSIZE 2048

int main(int argc, char *argv[])
{
	int iRet = 0;
        int sockfd;
        char buffer[MAXSIZE];
        char netbuffer[MAXSIZE];
        char rebuffer[MAXSIZE];
        struct sockaddr_in server_addr;
        struct hostent *host;
        int portnumber,nbytes;
        long lFileLength;
        
        int fd;
        int size;
        int w_size = 0;
        
        bzero(buffer,sizeof(buffer));
        bzero(netbuffer,sizeof(netbuffer));
        bzero(rebuffer,sizeof(rebuffer));
        
        FILE *fp;
        
        if(argc!=4)
        {
                fprintf(stderr,"Usage:%s hostname portnumber\a\n",argv[0]);
                exit(1);
        }

        if((host=gethostbyname(argv[1]))==NULL)
        {
                fprintf(stderr,"Gethostname error\n");
                exit(1);
        }

        if((portnumber=atoi(argv[2]))<0)
        {
                fprintf(stderr,"Usage:%s hostname portnumber\a\n",argv[0]);
                exit(1);
        }
        
       
        /* 客户程序开始建立 sockfd描述符  */
        if((sockfd=socket(AF_INET,SOCK_STREAM,0))==-1)
        {
                fprintf(stderr,"Socket Error:%s\a\n",strerror(errno));
                exit(1);
        }

        /* 客户程序填充服务端的资料       */
        bzero(&server_addr,sizeof(server_addr));
        server_addr.sin_family=AF_INET;
        server_addr.sin_port=htons(portnumber);
        server_addr.sin_addr=*((struct in_addr *)host->h_addr);

        /* 客户程序发起连接请求         */ 
        if(connect(sockfd,(struct sockaddr *)(&server_addr),sizeof(struct sockaddr))==-1)
        {
                fprintf(stderr,"Connect Error:%s\a\n",strerror(errno));
                exit(1);
        }
        
        /* 连接成功了           */
        
         //打开上传文件
        if((fp = fopen(argv[3],"rb")) == NULL)
        {
        	fprintf(stderr,"%s file dosen't opn.",argv[3]);
                exit(1);            
        }
        
        //获得文件长度
        fseek(fp,0L,SEEK_END);
        lFileLength = (long)ftell(fp);
        fseek(fp,0L,SEEK_SET);
      	fclose(fp);
 fprintf(stderr,"lFileLength:%d\n",lFileLength);       	
      	//将文件路径，文件长度存入netbuffer准备发送
      	bzero(netbuffer,sizeof(netbuffer));
        sprintf(netbuffer,"<filePath>%s</filePath><iFileLength>%d</iFileLength>",
        	argv[3],lFileLength);
      
        //向服务器发送数据文件路径，文件长度
	if(write(sockfd,netbuffer,strlen(netbuffer))==-1)
        {
                fprintf(stderr,"Write Error:%s\n",strerror(errno));
                exit(1);
        }
 fprintf(stderr,"netbuffer:%s\n",netbuffer);     
        //读文件内容
      	if( -1 == (fd = open(argv[3],O_RDONLY)) )
        {
        	fprintf(stderr,"%s file dosen't opn.",argv[3]);
                exit(1);            
        }
        while ( 1 )
        {
        	bzero(buffer,sizeof(buffer));
        	size = read (fd,buffer,sizeof(buffer)); 
        	if ( 0 == size ) //文件结束
        	{
        		break;
        	}
        	
        	//向服务器端发送文件内容
        	w_size = write(sockfd,buffer,strlen(buffer));
        	if( -1 == w_size )
	        {
	                fprintf(stderr,"Write Error:%s\n",strerror(errno));
	                break;
	        }
fprintf(stderr,"w_size:%d\n",w_size);  
	        
	}
	close(fd);	
    
	bzero(rebuffer,sizeof(rebuffer));
	
	//等待服务器端返回信息
        while(1)
        {
                if((nbytes=read(sockfd,rebuffer,MAXSIZE))==-1)
	        {
	                fprintf(stderr,"Read Error:%s\n",strerror(errno));
	                exit(1);
	        }	        
	        
	        if(0 != strlen(rebuffer))
	        {
	          rebuffer[nbytes]='\0';
	          printf("%s\n",rebuffer);
	           break;	
	        }
	 }
    
        /* 结束通讯     */
        close(sockfd);
        exit(0);
}