I'm struggling to see the advantage of going Fully Unicode in my input plugin - it seems I'll lose backwards compatibility, for a start, and all I'll gain is the headache of supporting Unicode filenames. If I just implement winampGetExtendedFileInfoW, will that do? Will Winamp keep sending me un-Unicode asdf~1 type filenames? Since winampGetExtendedFileInfo(W) are still undocumented, is that OK or likely to be broken?
Finally, why is winampGetExtendedFileInfo still used in preference to winampGetExtendedFileInfoW? If Winamp used the W one first, if available, I could provide both for better backwards compatibility for those tinfoil-helmet types using WA2.91.