Question

I wrote two simple programs server and a client using sockets in C++ (Linux). And initially it was a sample client-server application (echo-message sending and receiving the answer). Next, I changed the client in order to implement HTTP GET (now I do not use my sample server anymore). It works, but whatever buffer size I set, the client receives only 1440 bytes. I want to receive whole page into the buffer. I think that this is concerned with the TCP properties and I should implement some kind of cycle inside my client’s code to capture all the parts of the answer. But I don’t know what exactly I should do.

This is my code:

...
int bytesSent = send(sock, tmpCharArr, message.size()+1, 0);
// Wait for the answer. Receive it into the buffer defined.
int bytesRecieved = recv(sock, resultBuf, 2048*100, 0);
...

2048*100 is a buffer size and I think this is more than enough for the relatively small WEB-page used for testing. But as I mentioned, I receive only 1440 bytes.

What can I do with recv() function call to capture all the reply “parts” when the server’s response is larger then 1440 bytes?

Thanks in advance.

Answer 1

The buffer size is determined by factors outside your control (routers, ADSL links, IP stacks, etc.). The standard way to transmit large volumes of data is to call recv() repeatedly.