sockets and http

[ritka]

hi,
i wrote a little http client, that sends a GET request and it works mostly.
it sends the request and receives data from the server, first the header, then the content of the page. but the content it receives is incomplete. at the end a short part is always missing and i don't know whether my client doesn't receive the data or the server doesn't send it (because of the protocol).
here's the code:

#include <iostream>
#include <sys/socket.h>
#include <resolv.h>
#include <arpa/inet.h>

using namespace std;

int main()
{
    int s, error;
    struct sockaddr_in addr;

    if((s = socket(AF_INET,SOCK_STREAM,0))<0)
    {
        cout<<"Error 01: creating socket failed!\n";
        close(s);
        return 1;
    }

    addr.sin_family = AF_INET;
    addr.sin_port = htons(80);
    inet_aton("204.27.61.92",&addr.sin_addr);

    error = connect(s,(sockaddr*)&addr,sizeof(addr));
    if(error!=0)
    {
        cout<<"Error 02: conecting to server failed!\n";
        close(s);
        return 1;
    }

    char msg[] = "GET /beej/inet_ntoaman.html http/1.1\nHOST: retran.com\n\n";
    char answ[1024];
    //cin.getline(&msg[0],256);

    send(s,msg,sizeof(msg),0);

    while(recv(s,answ,1024,0)!=0)
        cout<<answ<<endl;

    close(s);
    cin.getline(&msg[0],1);
    return 0;
}

when i execute this i get the html sourcecode until this:

...
<td align="center"><a href="index.html">Beej's Guide to Network ProgrammGET /beej/inet_ntoaman.html http/1.1
HOST: retran.com

but it should be this

<td align="center"><a href="index.html">Beej's Guide to Network Programming</a></td><td align="right"><a href="inet_ntopman.html">Next&nbsp;&gt;&gt;</a></td>
</tr></table>

</body>
</html>

do you know what i did wrong?
furthermore i'd like to get some feedback about my code if you've something to mention.
thanks,
R.

[Galik]

I am not sure this will work if there is an error:

    while(recv(s,answ,1024,0)!=0)
        cout<<answ<<endl;

According to this: http://pubs.opengroup.org/onlinepubs/007904975/functions/recv.html

"Otherwise, -1 shall be returned and errno set to indicate the error."

I generally use something like:

    while(recv(s,answ,1024,0) > 0)
        cout<<answ<<endl;

Also you are outputting a raw char array answ[] with non null-terminated data. But cout<< is expecting null terminated data.

What I would do for this loop is something a bit like this:

	ssize_t len;
	while((len = recv(s, buf, 1024, 0)) > 0)
		std::cout.write(buf, len);
	std::cout << std::flush;

	if(len < 0)
	{
	    // O' Oh! Error!
	}

That way you only send out the number of bytes that you received.

[ritka]

ah, thank you.
with cout.get i get the full content of the page.
but for what is the cout<<flush ? i read it enforces a direct output of the stream, but the stream is still outputted directly, isn't it?

[Galik]

ritka wrote:

the stream is still outputted directly, isn't it?

Not necessarily.

[ritka]

ok, thanks.
the problem is solved.