How to send files through a socket connection?

[Radi0ShacK]

Hi all,
I just wanna know how to send a file through a socket connection in C language
"client request a certaion file on server and server send him this file" i work on both winsockets and bsd sockets "client ==> windows, server ==> *nix"
Thanks alot :)

[Narue]

>I just wanna know how to send a file through a socket connection in C language
The same way you would send any other stream of characters. Just pretend the socket is an output stream and copy the file to it.

[Radi0ShacK]

Thanks for reply,
but can u elaborate more through giving examples. can any one show me a simple code for very simple ftp client/server or any file transfer client/server in c lnaguage
Thanks again

[Narue]

Okay, your response begs two questions. Do you know how to read a file at all? And do you know anything about writing code for sockets?

[Radi0ShacK]

well, my answer for this smart question u asking me if i cant code why should i be asking about sockets? "yes i can"

[Narue]

>u asking me if i cant code why should i be asking about sockets?
No, I was asking you what you know so we don't waste time going over things that we don't need to. But if you want to be a dick about it, just say the word and I'll ignore you so that I can do more interesting things.

>"yes i can"
This answer is worthless. So, since you seem incapable of giving me enough information to properly help you, I'll require that you post a complete program that shows an honest attempt to solve the problem.

[MaSSaSLaYeR]

>u asking me if i cant code why should i be asking about sockets? No, I was asking you what you know so we don't waste time going over things that we don't need to. But if you want to be a dick about it, just say the word and I'll ignore you so that I can do more interesting things.

>"yes i can" This answer is worthless. So, since you seem incapable of giving me enough information to properly help you, I'll require that you post a complete program that shows an honest attempt to solve the problem.

Okay I got the same prob, so maybe you can help me :)

I'm first up trying to send some simple txt files via DCC

The sending part ain't working yet and I don't get any errors :/

Can you see why?

Thanks if you do!

//File stuff

FILE *fp;
    char read[500];
    char sendDCC[500];
    if((fp = fopen(fileLoc, "r"))==NULL) {
        printf("Cannot open file.\n");    
    }

    fseek(fp, 0,SEEK_END);
    sizeFile = ftell(fp);
    ltoa(sizeFile,strSizeFile,10);

//Socket listen-receive-accept

for(;;){
        //Listen
        listenfd = listen(sockfd, 10);
        if(listenfd == 0)
            printf("-->Listening on port %s...\n\n",MYPORT);
        else
            wprintf(L"### Listen failed with error: %ld\n\n", WSAGetLastError());

        FD_ZERO(&master);    // clear the master and temp sets
        FD_ZERO(&read_fds);
        FD_SET(sockfd, &master);
        // keep track of the biggest file descriptor
        fdmax = sockfd; // so far, it's this one
for(;;) {
            read_fds = master; // copy it
            if (select(fdmax+1, &read_fds, NULL, NULL, NULL) == -1) {
                wprintf(L"### Select failed with error: %ld\n\n", WSAGetLastError());
                closesocket(4);
            }

            // run through the existing connections looking for data to read
            for(i = 0; i <= fdmax; i++) {
                if (FD_ISSET(i, &read_fds)) { // we got one!!
                    if (i == sockfd) {
                        // handle new connections
                        addr_size = sizeof their_addr;
                        new_fd = accept(sockfd,(struct sockaddr *)&their_addr,&addr_size);
                        printf("accept");
                        if (new_fd == -1) {
                            wprintf(L"### Accept failed with error: %ld\n\n", WSAGetLastError());
                        }
                        else
                        {
                            FD_SET(new_fd, &master); // add to master set
                            if (new_fd > fdmax)
                            {    // keep track of the max
                                fdmax = new_fd;
                            }
                            printf("-->New connection from %s on socket %d\n\n", inet_ntop(their_addr.ss_family,&their_addr,remoteIP, INET6_ADDRSTRLEN),new_fd);
                        }
                    }
                    else
                    {
                        if ((nbytes = recv(i, buf, sizeof buf , 0)) <= 0) {
                            // got error or connection closed by client
                            if (nbytes == 0) {
                                // connection closed
                                printf("Socket %d hung up\n", i);
                            } else {
                                //get last error("recv");
                                printf("OK\n");
                            }
                            closesocket(i); // bye!
                            FD_CLR(i, &master); // remove from master set
                        }
                        else {
                            // we got some data from a client
                            lines = strtok(buf, "\n\r");

                            /*    do {
                            hostname = strtok(NULL, "\n\r");
                            } while (hostname[0] != 'H' || hostname[1] != 'o' || hostname[2] != 's' || hostname[3] != 't');

                            hostnamef = strtok(hostname, " ");
                            hostnamef = strtok(NULL, " ");
                            pagereq = strtok(lines, " ");
                            pagereq = strtok(NULL, " ");
                            */
                            for(j = 0; j <= fdmax; j++) {
                                // send to everyone!
                                if (FD_ISSET(j, &master)) {

                            
                                    char *mybufferke;
                                    setbuf(fp,mybufferke);
                                            //here
                                    //here
                                    //here
                                    //here
                                    //here
                                    //here
                                    //here

                                    bytes_sent = send(new_fd, mybufferke, sizeof(mybufferke), 0);
                                    if (bytes_sent > 0)
                                        printf("Send %i bytes\n\n",sizeof(bytes_sent));
                                    else if (bytes_sent == -1)
                                        wprintf(L"### Send failed with error: %ld\n\n", WSAGetLastError());

                                    // except the listener and ourselves
                                    if (j != sockfd && j != i) {

                                        if (send(j, buf, nbytes, 0) == -1) {
                                            wprintf(L"### Send failed with error: %ld\n\n", WSAGetLastError());
                                        }
                                    }
                                }
                            }
                        }
                    }
                }
            }