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PONot able to transfer binary files
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19735325
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0
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2
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7
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CreationDate
2013-11-01T21:00:40.803
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2013-11-06T20:03:37.257
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2013-11-01T21:14:34.223
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1024474
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2849082
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1
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-1
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160
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I am trying to build a server client code. The client can download any file from the server but I have problems with binary files This is my client code : <pre><code>#include <stdio.h> #include<sys/types.h> #include<sys/socket.h> #include<sys/time.h> #include<netinet/in.h> #include<arpa/inet.h> #include<string.h> #include<errno.h> #include<stdlib.h> #include<fcntl.h> #define Max_len 1025 //-------------------------- to replay for pecific secret simpol 0x55 char secret(char * str) { char sub=0x55; if(sub==str[0]) { sub=0xAA; return sub; } else { printf("server does not give the right secret code\n"); exit(0); } } //-------------------------warraper function for perror void error(char * str) { perror(str); exit(0); } int main ( int nof_arg, char **argv) { //------------------------define data types int sockfd,number,portno,val=0,fil_fd; //to store the file descreptore of socket char rec_lin [Max_len],f_name[20]="\0",car; // act as buffer struct sockaddr_in servaddr; char * read_one; FILE * file_ptr; //------------------------ welcome message identife the writer printf("\n\t Welcom the client \n\t Name: Eftikhar Emad \n\t ID: 20100175003\n\tsection #1: 9:15-10:15\n\n"); //------------------------ prepair the client to start connection if (nof_arg < 3) //check the number of entered arregument error("you need the IP and port number to connect please check them again\n"); portno=atoi(argv[2]); // convert the port from string to int if((portno<=22000) || (portno>=23000)) //check to see if the port numberif valiled error("your port number is out of range please try agin start with 22XXX\n"); if((sockfd=socket(AF_INET,SOCK_STREAM,0))<0) //socket creation error("Socket creation error"); bzero(&servaddr,sizeof(servaddr)); //static define for the server servaddr.sin_family=AF_INET; servaddr.sin_port = htons(portno); if(inet_pton(AF_INET,argv[1],&servaddr.sin_addr)<=0)//it can be used to check error("inet_pton error "); if((connect(sockfd,(struct sockaddr *)&servaddr,sizeof(servaddr)))<0)//connection error("connect error"); //------------------------------------start define the server valited bzero(rec_lin,sizeof(rec_lin)); read(sockfd,rec_lin ,sizeof(rec_lin)); printf("received the byte 0x55 from the server\n"); //will readonly one char car=secret(rec_lin); printf("Sending ack 0xAA to the server\n"); bzero(rec_lin,sizeof(rec_lin)); snprintf(rec_lin,sizeof(rec_lin),"%c",car); write(sockfd,rec_lin,1); //send 0xAA if 0x55 //-------------------------------------print the list from server read(sockfd,rec_lin,sizeof(rec_lin)); while(rec_lin[0]!= '\0') { read(sockfd,rec_lin,sizeof(rec_lin)); printf("%s\n",rec_lin); } //-------------------------after know the server start to ask and send file name printf("enter file name to download : "); gets(f_name); //rad file name from user snprintf(rec_lin,sizeof(rec_lin),"%s",f_name); write(sockfd,rec_lin,sizeof(rec_lin)); //send the file name to server bzero(rec_lin,sizeof(rec_lin)); //--------------------------------------check server reply 0/1 for finding or not read(sockfd,rec_lin,/*sizeof(rec_lin)*/1); int p; if(rec_lin[0]==0x31) //if file found inform the user,start,ending msg { //no creation to file unless it found on server printf("Received 1 from server %s exists\nStart downloading the file\n",f_name); fil_fd=open(f_name,O_RDWR| O_CREAT, S_IRUSR | S_IRGRP | S_IROTH); while((val=read(sockfd,rec_lin,sizeof(rec_lin)-1))>0) { p=strlen(rec_lin); // rec_lin[val]='\0'; write(fil_fd,rec_lin,/*sizeof(rec_lin)*/p+1); bzero(rec_lin,1049); } printf("Done Downloadng the file.......exit\n\n"); close(fil_fd); } else //if file not found terminate the connection { printf("file not found get ... connection will closed\n\n"); } // -----------------------------terminate connection if it Done in the right way close(sockfd); return 0; } </code></pre> and this is my server code : <pre><code>#include<stdio.h> #include<errno.h> #include<arpa/inet.h> #include<string.h> #include<netinet/in.h> #include<sys/types.h> #include<sys/socket.h> #include<stdlib.h> #include<fcntl.h> #include<netdb.h> #include<dirent.h> #define Max_len 1025 void error (char * str) { perror(str); exit(0); } int main (int argc, char ** arg) { / /------------------------- define data type int listenfd,connfd,clilen,portno,fil_fd,n; char buff[Max_len], *str,f_name[100],car=0xAA,h_IP[30],h_P[20]; struct sockaddr_in servaddr,cliaddr; DIR * ddir; struct dirent * ndir; //------------------------- socket intinalizing printf("\n\t Welcom the server \n\t Name: Eftikhar Emad \n\t ID: 20100175003\n\t section #1: 9:15-10:15\n"); if(argc != 2) //of user forget to insert the port number error("missing port number to complet establishment\n"); portno=atoi(arg[1]); //convert the port to int and check if it was within the rang if((portno<=22000) || (portno>=23000)) error("your port number not valid .... pleas insert one in reng (22000,22999)\n"); listenfd=socket(AF_INET,SOCK_STREAM,0); //creat the listing socket bzero((char *)&servaddr ,sizeof(servaddr)); servaddr.sin_family=AF_INET; //Ipv4 servaddr.sin_addr.s_addr=htonl(INADDR_ANY); servaddr.sin_port=htons(portno); bind(listenfd,(struct sockaddr *)&servaddr,sizeof(servaddr));//bind the liten socket to specific port listen(listenfd,5); //-------------------------- server start to wait to handle requests for(;;) { printf("server wait for connections\n"); bzero((char *)&cliaddr ,sizeof(cliaddr)); //clear the previus client information clilen=sizeof(cliaddr); //client informaton container connfd=accept(listenfd,(struct sockaddr *)&cliaddr,&clilen); int f=fork(); //start of fork() if(f==0) { close(listenfd); if(connfd<0) error("error in accept this connection\n"); //--------------------------------------- //start the secret hand chacking bzero(buff,sizeof(buff)); getnameinfo((struct sockaddr *)&cliaddr,sizeof(cliaddr),h_IP,sizeof(h_IP),h_P,sizeof(h_P),0); printf("Sending byte 0x55 to client with IP %s and port of %s\n",h_IP,h_P); //get the IP AND port# of the client snprintf(buff,sizeof(buff),"%c",0x55); write(connfd,buff,sizeof(buff)); //--------------------------------------- //read file name car=0xAA; read(connfd,buff,sizeof(buff)); printf("received 0XAA from client \n"); if(car==buff[0]) { //------- send the list to the client snprintf(buff,sizeof(buff),"select file to download it\n"); write(connfd,buff,sizeof(buff)); ddir=opendir("."); if(ddir==NULL) {printf("error\n");exit(0);} while((ndir=readdir(ddir))!=NULL) {//printf("%s\n",ndir->d_name); snprintf(buff,sizeof(buff),"%s",ndir->d_name); printf("%s\n",buff); write(connfd,buff,sizeof(buff)); } write(connfd,"\0",1); closedir(ddir); read(connfd,buff,sizeof(buff)); //get the name after get 0xAA strncpy(f_name,buff,sizeof(buff)-1); } else { printf("this is not secure client\n");break;} //-------------------------------------- if file found send 1 else 0 fil_fd=open(f_name,O_RDONLY); //file opent to be read only if(fil_fd < 0) { snprintf(buff, sizeof(buff),"%d",0); write(connfd,buff,1); printf("file is not found\n"); //retminate connection only break; } else { snprintf(buff, sizeof(buff),"%d",1); write(connfd,buff,sizeof(buff)); printf("file exists.Send %s to client\n",buff); //-----------------------------------reading and sending while((n=read(fil_fd,buff,sizeof(buff)-1))>0) { buff[n]='\0'; write(connfd,buff,/*sizeof(buff)*/n+1); //sending the file process bzero(buff,sizeof(buff)); }//end of uploading printf("end download thf file"); close(fil_fd); }//end of if_else close(connfd); exit(0); }//end of child code else { //wait(NULL); printf("-------------------------------\n"); close(connfd); } }//end of for() //--------------------------------------------prepair the server connection close(listenfd); exit(0); return 0; }//main() </code></pre> this code works fine if I use it with "file.txt". I want to use it with binary files without using <code>fread()</code> or <code>fwrite</code> or <code>fopen</code>. Is there any way to do it?
Tags
<c><sockets><network-programming><binaryfiles>
Title
Not able to transfer binary files
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