Network port listening

I am writing an application (an ins开发者_运维百科tant messenger). I would like to know whether IOS supports application to listen to a particular ports for incoming packet continuously (when the application is active not suspend).

Thanks.

Short answer: yes

Long answer: Chris provided a link how to deal with sockets using CFNetwork Framework.
I'd like to add the hint for cocoa-asyncsocket, a light-weight object-orientated wrapper for that framework. A true time-saver.

Survey says: yes.

http://oreilly.com/iphone/excerpts/iphone-sdk/network-programming.html