I have a Linksys NSLU2 (a device for sharing USB devices over ethernet) attached to my network. It runs some custom firmware that includes an FTP server which allows me to transfer files to and from my PVR (digital video recorder). All works wonderfully and I use Opus FTP to copy files back and forth.
The FTP server allows you to operate in 'turbo' mode, which gives a faster connection to the PVR at the expense of stopping it from doing anything else, which is why I don't have it enabled by default. However it is possible to enable/disable turbo mode on the fly by sending FTP commands like 'site turbo' (toggles on/off), 'site turbo 1' (sets to on) or 'site turbo 0' (sets to off).
And so to my question: can I configure a button in Opus to send these commands or do I have to switch to another FTP client?
There's no way to do that right now. You could file a feature request for the ability to specify custom commands that get run after connection to a site and see what GPSoft think of the idea.
Some random asides about the NSLU2 that don't help you get what you want but I couldn't help but talk about:
I used to use an NSLU2, still have it somewhere. I stopped using it when I realised the CPU in it was so slow it couldn't write at anywhere near the speed that a USB2.0 HDD should reach on a 10mbit network (let alone a 100mbit one). Quite disapointing for what is otherwise a nice bit of kit. (It's a little embedded Linux box. You can telnet to it, install packages and everything.)
The other thing that annoyed me was that the official firmware used a version of Samba that didn't understand Unicode filenames. Dunno if that has changed now. You can replace it with a different version, of course, if you know what you're doing with Linux.
There is simple a hack (can't recall whether it's software or hardware) that lets the Slug operate about twice as fast, but apparently it gets quite hot if you do that. In any case, despite the fact that the PVR that I attach to it is a hard drive in a box it doesn't transfer anywhere near as fast as USB 2.0, so the Slug is fine for my use. It doesn't have LEDs like studio floodlights and doesn't whirr, beep or honk either which makes it ideal for plonking next to the TV.
Mine is running some firmware called uNSLUng, which I managed to install while knowing virtually nothing about Linux. It has a package installed that lets it act as an FTP server for my Topfield PVR which is pretty damn clever seeing as the Toppy isn't a standard USB device.
I guess I'll file a feature request and use Filezilla for now.