Handling asynchronous receive with a TCP socket

[Overv]

Hi,

I'm currently using a thread to process a queue with asynchronous Connect and Send operations. Now I also want to make receive asynchronous. The problem with receiving however is that now it doesn't block the main program, but it blocks the asynchronous processing queue, so my socket still becomes useless until I receive something. What is the equivalent of "select" with SFML?

This is my current thread code:

Code: [Select]

void TCPThread( void* userdata )
{
TCPSocket* sock = (TCPSocket*)userdata;

while ( true )
{
if ( sock->queue.size() > 0 )
{
TCPOperation op = sock->queue[0];

switch ( op.op )
{
case 0:
sock->connected = false;
sock->connected = sock->sock.Connect( op.arg2, op.arg1, op.arg4 ) == sf::Socket::Done;
break;

case 1:
sock->sock.Send( op.arg1, op.arg3 );
break;
}

sock->queue.pop_front();
}
}
}

Also, what is the use of SetBlocking? There is no way to check if you're connected yet.

[Laurent]

What is the equivalent of "select" with SFML?

sf::Selector.

Also, what is the use of SetBlocking? There is no way to check if you're connected yet.

Why do you need to know if you're connected?
Calling Receive on a non-blocking socket will return a useful status: Done, Error, NotReady or Error.

[Overv]

sf::Selector.

I tried using that, but VS told me GetSocketsReady doesn't exist.

Why do you need to know if you're connected?
Calling Receive on a non-blocking socket will return a useful status: Done, Error, NotReady or Error.

What if I want to check if I'm connected without sending anything? Also, making my socket non-blocking and doing the following makes the program loop infinitely.

Code: [Select]

while ( sock.Send( data, sizeof( data ) ) != sf::Socket::Done );

[Laurent]

I tried using that, but VS told me GetSocketsReady doesn't exist.

Which version of SFML are you using?

What if I want to check if I'm connected without sending anything?

This is not possible in SFML 1, but it is implemented in SFML 2. But this is not related to non-blocking mode. You shouldn't need it more with non-blocking sockets.

Also, making my socket non-blocking and doing the following makes the program loop infinitely.

You should loop while you get sf::Socket::NotReady, but break on sf::Socket::Error and sf::Socket::Disconnected.

[Overv]

I tried using that, but VS told me GetSocketsReady doesn't exist.

Which version of SFML are you using?

SFML 1.6

The loop problem seems to be a VS2010 problem, nevermind.

[Laurent]

In SFML it's Selector::GetSocketReady, not GetSocketsReady

[Overv]

In SFML it's Selector::GetSocketReady, not GetSocketsReady

Oh, alright. Then you need to correct the tutorial
http://www.sfml-dev.org/tutorials/1.2/network-selector.php

[Laurent]

This is the tutorial for SFML 1.2...

WARNING : this is the documentation for an old version of SFML ; the documentation for the latest official release is available through the main menu

[Overv]

This is the tutorial for SFML 1.2...

WARNING : this is the documentation for an old version of SFML ; the documentation for the latest official release is available through the main menu

Sorry for wasting your time  :roll:

[Ashenwraith]

Yeah that's kinda what's crazy when you are using constantly evolving code.

You have to dig through the sources for the best documentation. I was surprised to see a mini-tutorial/example in a header file so maybe there is something more if you look?

[Laurent]

You have to dig through the sources for the best documentation. I was surprised to see a mini-tutorial/example in a header file so maybe there is something more if you look?

This is just for non-released versions for which I didn't generate/upload the documentation yet. Otherwise, you're not supposed to dig through the source code to find it.