Problem with Socket.h in C

Hello all,
I am trying to make a small server which is connectable trough a telnet session. I am following Beej's guide but I am stuck with a error I do not seem to get fixed.

when I run this source I am able to connect, I see the msges in server console and on the client. But when I start typing it only displays the first letter. What I would like is that it receives data when I hit enter.

At this moment when I type data for example it shows a d immediatly but not the rest

Code:

	#include <string.h>
    #include <sys/types.h>
    #include <sys/socket.h>
    #include <netinet/in.h>

    #define MYPORT 3490
	#define MAXDATASIZE 100


    int main()
    {
	char buf[MAXDATASIZE];
    int sockfd, new_fd, aant_bytes;  /* luisteren op sock_fd, nieuwe verbinding op new_fd */
    struct sockaddr_in mijn_addr;   /* mijn adresinformatie */
    struct sockaddr_in hun_addr; /* connector's adresinformatie */
    int sin_size;

	// vergeet de foutafhandeling voor socket() niet | errno is fout | geeft -1:
    sockfd = socket(AF_INET, SOCK_STREAM, 0); // doe wat foutafhandeling!

	mijn_addr.sin_family = AF_INET;         // host byte volgorde
    mijn_addr.sin_port = htons(MYPORT);     // short, netwerk byte volgorde
    mijn_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    memset(&(mijn_addr.sin_zero), '\0', 8); // de rest van de struct op nul

    // vergeet de foutafhandeling voor bind() niet | errno is fout | geeft -1:
    bind(sockfd, (struct sockaddr *)&mijn_addr, sizeof(struct sockaddr));


    //server laten luisteren | TODO Errorhandling | errno is fout | value -1
    printf("server: I am now listening on %d \n", MYPORT);
	listen(sockfd, 10);

    while(1){
		sin_size = sizeof(struct sockaddr_in);
        if((new_fd = accept(sockfd,(struct sockaddr*)&hun_addr,&sin_size))== -1){
			perror("accept");
            continue;
        }

		printf("server: Received connection from: %s \n",inet_ntoa(hun_addr.sin_addr));
	
		if (!fork()) { /* dit is het kind proces */

			if (send(new_fd, "Welcome to my postFix Calculator. \n \n", 36, 0) == -1){
				perror("send");
			    close(new_fd);
				exit(0);
			}
		
			if ((aant_bytes = recv(new_fd, buf, MAXDATASIZE-1, 0)) <= 0) {
				// got error or connection closed by client
				if (aant_bytes == 0) {
					// connection closed
					printf("selectserver: socket hung up\n");
				} 
				else {
					perror("recv");
				}
			}
			else{
			// we got some data from a client
			printf("server: %s \n ",buf);
			} 
		}
	}
return 0;
}

I've been messing with this all night and I just don't seem to get it right.

Kind regards,
Yuushi Celeritas

What happens if you call recv() in a loop?

--
Mats

changed it to:

Code:

 
			while ((aant_bytes = recv(new_fd, buf, MAXDATASIZE, 0)) > 0) {

			// we got some data from a client
			printf("%s",buf);
			}

which seems to work now I type data hit enter and it shows something like:
http://www.digital-it.nl/temp/sample.jpg

after that every key I hit gets displayed below that text:
http://www.digital-it.nl/temp/sample1.jpg

:S

kind regards,
Yuushi

I think a normal telnet connection sends a char at a time, so that would be why you are receving the packets as one char at a time.

So just pack together a bunch of chars until you get a newline, and then process that.

--
Mats

that makes sense but I don't really have a clue how to do that, I assume you retrieve the chars in a for loop and put them in a variable untill buf == "\n"?

wouldn't slamming them together be a problem if the chars look weird like in the images?

Kind regards,
Yuushi

I believe your "weird" characters come from the fact that buf[] is not nul-terminated, so printf just prints a bunch of rubbish after your actual data. [It looks to me like you happen to have a 32-bit value where the uppermost byte is zero, thus getting your char, then two "random" characters printed, and the zero acts as a termination - it is probably some return-address or a pointer to something that happens to be on the stack - don't rely on this behaviour to be consistant if you modify your application!]

--
Mats

thnx