[Spice-devel] Questions on usbredir + XSpice redux, libusb anyone?

[Jeremy White]

Hey Hans,

> "most Linux applications ... are going to use libusb to access the USB
> devices."
> 
> That is not true, applications using libusb rather then a kernel driver
> are the exception not the rule. Basically the only major applications using
> libusb are sane (scanners) and libgphoto2 (still photo cameras), anything
> else, webcams, usb audio, hid devices, usb-sticks, usb-harddisks, dvb
> receivers,
> printers (*), etc. is all using kernel drivers.

Thanks for the reply; it's evident I don't have a vivid imagination for
the world of USB devices :-/.

> 
> *) Yes some printer backends may use libusb, this is usually done to get
> some extra info from the printer using vendor specific commands, the actual
> printing is usually still done via /dev/lp and thus through a kernel
> driver.

Are you sure?  A (perhaps naive) look at the CUPS source code strongly
suggests that most usb device access now goes through libusb for CUPS.

Cheers,

Jeremy