C Sockets - recv() problem

I have a problem with the recv() function. I wrote a simple program studying Beej Guide and made a simple program that connects to yahoo.com on port 80 and runs the GET HTML command. Now doing this with netcat or telnet displays a lot of garbage data, actually retrieves the webpage for me. But using my program just retrieves a small amount of data. Can anyone help? Here is the code

Code:

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#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <errno.h>
#include <strings.h>
#include <netinet/in.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/wait.h>

#define DEST_PORT 80
#define DEST_IP "68.142.197.74"
#define MAXDATASIZE 300

int main()
{
        int numbytes;
        char buff[MAXDATASIZE];
        int my_socket; //creeaza variabila ce va stoca socket-ul
        struct sockaddr_in destination_address; //stocheaza adresa de conectare
       
        if ((my_socket = socket(AF_INET, SOCK_STREAM, 0)) == -1)
        {
                perror("socket");
                exit(1);
        }
       
        destination_address.sin_family = AF_INET; //host to byte order
        destination_address.sin_port = htons(DEST_PORT); //short, network to byte order
        destination_address.sin_addr.s_addr = inet_addr(DEST_IP); //destination ip
        bzero(&(destination_address.sin_zero), 8); //zero the rest of the struct

        if ((connect(my_socket, (struct sockaddr*)&destination_address, sizeof(struct sockaddr))) == -1)
        {
                perror("connect");
                exit(1);
        }
       
        if (send(my_socket, "GET HTML\n",9, 0) == -1)
        {
                perror("send");
                exit(1);
        }
       
        if ((numbytes = recv(my_socket, buff, MAXDATASIZE, 0)) == -1)
        {
               
                perror("recv");
                exit(1);
        }
       
        buff[numbytes] = '\0';
       
        printf("Received: %s", buff);
       
        close(my_socket);

        return 0;
}

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You are only calling recv() once. You need to call it in a loop to get all the data from the server.

If I use a loop I cannot do an error test, or can I use while(if( .... ?

The connection will be closed by the server when all the data is sent so you just need to keep recieving data untill either you get SOCKET_ERROR or 0. Since recv returns the number of bytes recieved we use this value to incriment a pointer and decrease the maximum buffer size so we don't overrun.

Code:

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ptr=buff;
for{;;)
  int nSize=MAXDATASIZE;
  int nRet = recv(my_socket, ptr, nSize, 0)
  if (nRet==SOCKET_ERROR || nRet==0)
      {//error or done.
        break;
      }
  nSize-=nRet;
  ptr+=nRet;
}

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