simple hello world SERVER/CLIENT

im trying to send the string "hello world"
from one program to the other - via loopback
but the client is printing garbage...
please help!

ps: conio.h and getch() are just to hold the window open in borland compiler

CLIENT

Code:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include<winsock.h>
#include<conio.h>

#define MAXRCVLEN 500
#define PORTNUM 2343

int main(int argc, char *argv[])
{
    char buffer[MAXRCVLEN + 1]; /* +1 so we can add null terminator */
    int len, mysocket;
    struct sockaddr_in dest; 

    mysocket = socket(AF_INET, SOCK_STREAM, 0);
 
    memset(&dest, 0, sizeof(dest));                /* zero the struct */
    dest.sin_family = AF_INET;
    dest.sin_addr.s_addr = inet_addr("127.0.0.1"); /* set destination IP number */ 
    dest.sin_port = htons(PORTNUM);                /* set destination port number */

    connect(mysocket, (struct sockaddr *)&dest, sizeof(struct sockaddr));
 
    len = recv(mysocket, buffer, MAXRCVLEN, 0);

    /* We have to null terminate the received data ourselves */
    buffer[len] = '\0';

    printf("Received %s (%d bytes).\n", buffer, len);

    closesocket(mysocket);
    getch();
    return EXIT_SUCCESS;
}

SERVER

Code:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include<winsock.h>

#define PORTNUM 2343

int main(int argc, char *argv[])
{
    char msg[15] = "Hello World !\n";
 
    struct sockaddr_in dest; /* socket info about the machine connecting to us */
    struct sockaddr_in serv; /* socket info about our server */
    int mysocket;            /* socket used to listen for incoming connections */
    int socksize = sizeof(struct sockaddr_in);
 
    memset(&dest, 0, sizeof(dest));    /* zero the struct before filling the fields */
    serv.sin_family = AF_INET;         /* set the type of connection to TCP/IP */
    serv.sin_addr.s_addr = INADDR_ANY; /* set our address to any interface */
    serv.sin_port = htons(PORTNUM);    /* set the server port number */    
 
    mysocket = socket(AF_INET, SOCK_STREAM, 0);
 
    /* bind serv information to mysocket */
    bind(mysocket, (struct sockaddr *)&serv, sizeof(struct sockaddr));
 
    /* start listening, allowing a queue of up to 1 pending connection */
    listen(mysocket, 1);
    int consocket = accept(mysocket, (struct sockaddr *)&dest, &socksize);
 
    while(consocket)
    {
        
 
        printf("Incoming connection from %s - sending welcome\n", inet_ntoa(dest.sin_addr));
        send(consocket, msg, strlen(msg), 0);
 
        
    }
    closesocket(consocket);
    closesocket(mysocket);
    return EXIT_SUCCESS;
}

Did you have a question in your post some place?


Quzah.

Originally Posted by quzah

Did you have a question in your post some place?


Quzah.

at the top
the bit that says

im trying to sent the string "hello world" from one program to the other via loopback but the client is printing garbage...
please help!

You mean the part that you edited in there? What sort of "garbage"? Does the string make it there at all? Is it just random info? What are you getting for len? You might consider actually checking the return values of all of those handy functions...


Quzah.

Originally Posted by quzah

You mean the part that you edited in there? What sort of "garbage"? Does the string make it there at all? Is it just random info? What are you getting for len? You might consider actually checking the return values of all of those handy functions...


Quzah.

it was edited for you honey haha

its just random ........e that changes every time i run the client
i got it off a tutorial and modified it for windows:
C Programming/Networking in UNIX - Wikibooks, collection of open-content textbooks

So start checking the return values of your functions against what they're supposed to return to see where it's failing.


Quzah.

is anyone out there able to help?

Originally Posted by goonmaster

im trying to send the string "hello world"
from one program to the other - via loopback
but the client is printing garbage...
please help!

ps: conio.h and getch() are just to hold the window open in borland compiler

CLIENT

Code:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include<winsock.h>
#include<conio.h>

#define MAXRCVLEN 500
#define PORTNUM 2343

int main(int argc, char *argv[])
{
    char buffer[MAXRCVLEN + 1]; /* +1 so we can add null terminator */
    int len, mysocket;
    struct sockaddr_in dest; 

    mysocket = socket(AF_INET, SOCK_STREAM, 0);
 
    memset(&dest, 0, sizeof(dest));                /* zero the struct */
    dest.sin_family = AF_INET;
    dest.sin_addr.s_addr = inet_addr("127.0.0.1"); /* set destination IP number */ 
    dest.sin_port = htons(PORTNUM);                /* set destination port number */

    connect(mysocket, (struct sockaddr *)&dest, sizeof(struct sockaddr));
 
    len = recv(mysocket, buffer, MAXRCVLEN, 0);

    /* We have to null terminate the received data ourselves */
    buffer[len] = '\0';

    printf("Received %s (%d bytes).\n", buffer, len);

    closesocket(mysocket);
    getch();
    return EXIT_SUCCESS;
}

SERVER

Code:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include<winsock.h>

#define PORTNUM 2343

int main(int argc, char *argv[])
{
    char msg[15] = "Hello World !\n";
 
    struct sockaddr_in dest; /* socket info about the machine connecting to us */
    struct sockaddr_in serv; /* socket info about our server */
    int mysocket;            /* socket used to listen for incoming connections */
    int socksize = sizeof(struct sockaddr_in);
 
    memset(&dest, 0, sizeof(dest));    /* zero the struct before filling the fields */
    serv.sin_family = AF_INET;         /* set the type of connection to TCP/IP */
    serv.sin_addr.s_addr = INADDR_ANY; /* set our address to any interface */
    serv.sin_port = htons(PORTNUM);    /* set the server port number */    
 
    mysocket = socket(AF_INET, SOCK_STREAM, 0);
 
    /* bind serv information to mysocket */
    bind(mysocket, (struct sockaddr *)&serv, sizeof(struct sockaddr));
 
    /* start listening, allowing a queue of up to 1 pending connection */
    listen(mysocket, 1);
    int consocket = accept(mysocket, (struct sockaddr *)&dest, &socksize);
 
    while(consocket)
    {
        
 
        printf("Incoming connection from %s - sending welcome\n", inet_ntoa(dest.sin_addr));
        send(consocket, msg, strlen(msg), 0);
 
        
    }
    closesocket(consocket);
    closesocket(mysocket);
    return EXIT_SUCCESS;
}

You seriously need to use getaddrinfo.

if any socket programmers understand this code i would appreciate the help.

Did you read what I posted? If you write cleaner code, more people will respond to you. I'm not trying to be mean or anything, but this troubled me quite a bit when I was beginning (which I still am).

First of all, you have to initialize winsock in your client and server app...

Code:

WSADATA wsaData;
    WORD wVersionRequested = MAKEWORD(1,1);
    int nRet;
    	
	// Init WinSock
    nRet = WSAStartup(wVersionRequested, &wsaData);
    if (nRet)
    {
		fprintf(stderr,"\nError initializing WinSock\n");
		return -1;
    }

	// Check version
	if (wsaData.wVersion != wVersionRequested)
	{
		fprintf(stderr,"\nWinSock version not supported\n");
		return -1;
	}

and link your code with ws2_32.lib