Could you be more descriptive? "interacting with the server" is so vague it could have any number of responses that you may not consider relevant. Connecting to the server with an FTP client would be considered "interacting with the server".
By "new" methods, are you referring to features in future versions of ioFTPD or methods in the current version you aren't aware of? (There's a lot more than Tcl and PHP.)
If it's an external process communicating with ioFTPD you can use IPC (shared memory/window messaging). If the external process is event driven (executed by ioFTPD on certain events, like OnUploadComplete etc.) there are commands that can be sent to ioFTPD via stdout (!buffer/!change etc.).
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