On Sun, Nov 23, 2003 at 08:50:45PM -0500, Michael E. Mercer wrote: > Hello peoples, > > I posted this to questions with no reply, I was hoping > someone here may be able to give some insight. > > > Question: Should I be able to open /dev/ugen0 more than once? > > I am using FreeBSD 4.9-Stable, libusb-0.1.7. > >From reading the libusb docs, you must open the device for each > interface you want to acquire. However, once it is opened once, it can't > be opened again. > > Furthermore, calls to usb_find_devices() shows that /dev/ugen0 has > disappeared. Investigation on how they(libusb) finds devices, shows they > are trying to open the device read only... this is where it tries to > open it the second time. This second try fails and therefore libusb > thinks the device was removed. > > Question: Is this the correct behavior?
Yes - this is correct. A client using ugen on a multiple interface only need to open /dev/ugen? for probing only - the work should be done using the interface specific endpoints /dev/ugen?.? Opening /dev/ugen? read-only makes no sense, because there is no read only access possible - /dev/ugen? is for the control endpoint which always means sending commands to the device. -- B.Walter BWCT http://www.bwct.de [EMAIL PROTECTED] [EMAIL PROTECTED] _______________________________________________ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "[EMAIL PROTECTED]"
