Hello all, How do you set a socket to non-blocking/blocking status in linux? In win32 I used ioctlsocket(...), what is the linux equivalent of this? Thank You!

fcntl(socket,F_SETFL,O_NONBLOCK);

Are you sure that you wish to use non-blocking I/O though?
I'm of the opinion that it's generally better to create a new thread for doing concurrent I/O and use blocking I/O operations.

Threading brings with it all the synchronisation issues however, not to mention isn't as scalable. The latter may not often be a problem but the former may be.

The HTTP GET sample runs on Windows and Linux, and uses non-blocking sockets. It contains a header (sock_port.h) which makes socket programming more portable.

The specific strategy used on Linux is to not change the socket, but instead pass the MSG_DONTWAIT flag. Anyway, if you're doing Linux and Windows programming, you might want to look at that sample.