[sane-devel] sane_get_devices and sanei_usb_init

[ABC]

> http://www.sane-project.org/html/doc012.html
> 4.3.3 sane_get_devices
> ...
> This function can be called repeatedly to detect when new devices
> become available.

Nice writing but it is not possible with usb now, because sanei usb
infrastructure get list of devices only when sanei_usb_init() is called.
And it is not possible to call sanei_usb_init() more than once without
breaking already opened devices.