retrieving detailed usb midi device information on windows xp

Question

The function midiOutGetDevCaps returns a structure MIDIOUTCAPS. I'd need more specific information when querying a usb midi device on windows xp, in particular I'd need the information displayed under "Location" when opening the respective device using the Device Manager. I need this information in order to programmatically distinguish between several MIDI Interfaces connected to a computer. Using midiOutGetDevCaps, I uniformly get "USB Audio Device" for every midi usb interface connected to the computer, so distinguishing between the interfaces is impossible. To make matters worse, this string is localized, so e.g. on a German Windows you'll get "USB Audiogerät" instead of "USB Audio Device".

Answer 1

I guess it depends on how desperate you are. I've had my own run in with USB devices. In my case I needed to enumerate certain USB COM port related devices . . . regardless if they are currently attached to the system or not.

It is all company proprietary code, sorry I cannot post it, but the search for all information regarding USB related devices starts here (Perl):

$hostnamePrefix = "//$hostname/";
my $baseKey = "${hostnamePrefix}HKEY_LOCAL_MACHINE/System/CurrentControlSet/";
my $regVidList = Win32::TieRegistry->new("${baseKey}Enum/USB/", $optionsRef);

If memory serves me it is a reasonably straight forward structure. I believe you actually have to loop through two separate sections of the registry to get everything you need . . . if you are desperate enough to attempt this, I'm happy to answer questions where I can, but posting code would required approval from our legal department. (Not impossible, but it would take weeks to obtain.)

Also, while this will work on XP . . . I have no idea how it will work on Win7. (I don't know either way, nobody has tried it yet that I am aware of.)

Coding this was not that bad (resulting Perl Script is around 1000 lines of code which is almost 50% comments), but working out all the relationships between the keys and the special cases took several days.