"[EMAIL PROTECTED]" <[EMAIL PROTECTED]> writes: > I am relatively new to Python, and wanted to see if this is even > possible, and if so how to go about implementing it. What I'm looking > to do is create a client/server application that does the following: > > 1) System2 listens on port > 1023 > 2) System1 connects to System2 and sends traffic to it - based on the > traffic it receives (i.e. a special string), System2 executes > command-line commands and returns the output to System1.
You're asking how to write a TCP server in general. You might look at the SocketServer module in the standard library, which gives a reasonable framework for that kind of server. However, its documentation is not very good. Alex Martelli's "Python Cookbook" may have some better examples. If you want your server to be able to handle multiple client sessions simultaneously, use SocketServer.ThreadingMixin (for multiple threads) or SocketServer.ForkingMixin (multiple processes). Beware that this stuff is not easy for beginners, unless you've had experience writing servers in other languages (maybe Java). There's another issue too, especially if your app is a virus scanner: you have to think very hard about what happens if a malicious client connects to your server (a virus scanning app is an unusually juicy target for such attacks). It's extremely easy to leave security holes open (the viruses themselves typically exploit such holes in Windows) so you have to develop a paranoid attitude about what kinds of things the attacker can try and how you can defend. Using Python puts you one step ahead of Windows, since you're mostly immune to buffer overflow bugs, a very common vulnerability. But it's still an area full of hazards and not so good for beginners. This is good bedtime reading: http://www.dwheeler.com/secure-programs/ -- http://mail.python.org/mailman/listinfo/python-list