Re: [Libusb-devel] multiple call of claim_interface from two different processes behaves undefined

[David <do...@gm...>]

Daniel Drake wrote:
> David wrote:
>> I'm confused about the claim_interface function. I thought when a 
>> process opens
>> a device and claims an interface this process has exclusive rights to 
>> the interface endpoints.
>> When another process opens the device the claim_interface function 
>> works also but the
>> behavior when receiving bytes from the interface endpoint is undefined 
>> (sometimes the first
>> process gets the bytes and sometimes the second).
> 
> Can't reproduce this.
> Are you definitely claiming the same interface in both programs?
> 
> I just ran libusb's dpfp example, which started running and waiting for 
> fingerprint scans. Then I ran it again in another terminal, and the 2nd 
> one bailed out immediately:
> 
> libusb:debug [libusb_claim_interface] interface 0
> usb_claim_interface error -6
> libusb:debug [libusb_close]
> 
> -6 is LIBUSB_ERROR_BUSY
> 
> Seems to be working here. Linux 2.6.25.
> 
> Daniel
> 

Sorry, you're right. I claimed two different interfaces on the same 
device. Thanks for you're help.

David