Is there any document out there on the internet describing how access the json-rpc interface of the bitcoind daemon? In my case, my application is written with C++, and I want access this interface with this language. In my Kubuntu system, I have run bitcoin-qt and it's listenning on port 8333. I create a bitcoin.conf file on my data directory setting an username and a password. Now I want to know how access this interface using C++.

ps.: I should note that I know about libbitcoin library. I ask for the specification because I am trying find a simplest approach, maybe allowing me write my code in only one or two source code files.