[sane-devel] Proposed patch for the snapscan semaphore issue

[Oliver Schwartz]

Hi,

> The patch only works for libusb devices. Applying it as is means the
> backend will now fail hard if you're using a non-pthread build of SANE
> with a non-libusb access method.
>
> I'm not sure such a combination exists. If I'm not mistaken, OS/2 uses
> pthread by default, so does OS X and all other OSes use libusb.

If I read your patch correctly it would also break support for the  
old USB access by device /dev/usb/scanner0 on Linux 2.4.x (or was it  
2.2.x?) without libusb. Maybe it's a good idea to fall back to the  
old ftok() method if the device name doesn't start with "libusb:".

Apart from that the patch looks ok to me.

Regards,

Oliver