I think you are looking for the connect command.
https://en.bitcoin.it/wiki/Running_Bitcoin#Command-line_arguments
Most of those you can put in a config file too.
https://en.bitcoin.it/wiki/Running_Bitcoin#Command-line_arguments
Most of those you can put in a config file too.
Not at all what he is looking for.
Bitcoin Core-based wallets have a communication mechanism, where commands can be issued to the running client over the network, called RPC (remote procedure call).
You first must turn on the server component of Bitcoin by using server=1 in the config file or as a command line option, and also must set an rpcuser/password. Then in the config file you must allow the correct IP address netmasks for only local machines and networks that are allowed to connect. An example config file with these options individually documented is here: http://we.lovebitco.in/bitcoin-qt/configuration-file/
Once that is on, you can test communications locally by running a second bitcoind to issue commands (which also functions as a simple RPC client), commands like "bitcoind help".
For programmatic access, you can take a look at documents like:
https://en.bitcoin.it/wiki/API_reference_%28JSON-RPC%29
http://upcoder.com/7/bitcoin-rpc-from-python/
