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Re: (no subject)

John and Kris-
Maybe what is happening is that you have Classic Environment running and it "owns" the device
when you first attempt to open it.

This might shed some light on what is happening:

http://developer.apple.com/documentation/DeviceDrivers/Conceptual/ ClassicUSBDeviceArb.html

Hope this helps...
Regards,
Stephen Reid, Technical Lead, TI Connect for OS X
Texas Instruments Incorporated


On Thursday, October 2, 2003, at 10:08  AM, Kris Daniel wrote:

This happened to me as well. I noticed that if I called USBDeviceOpen(), or USBInterfaceOpen(), I'd usually get an error on the first call. Just to be stubborn, I tried calling the open command again after it failed, and it opened successfully.

I don't have an explanation for it (possibly uninitialized variable?), it works, so I moved on. At the very least, it's an idea to try.

Kris Daniel
Line 6, Inc.


On Thursday, October 2, 2003, at 07:32 AM, John Cebasek wrote:

Hi All:

Excuse the newbie question, I've inherited some code...

I have been working on the device driver for our product and have run
into a little bit of a brick-wall.  To summarize, everything is going
OK until I try and 'claim' the device.  When I call
USBInterfaceOpenSeize() I'm getting an error back
kIOReturnExclusiveAccess (E000002C5).  When USB Prober is running, it
reports "handleOpen failing because super::handleOpen failed (someone
already has it open)".

Sounds like someone (the OS??) has already claimed the device and won't
release it.

Is my hypothesis correct? What can I do about it? If my hypothesis
isn't correct, then any ideas?

If you could point me in the right direction, it would be appreciated.

Thanks for your time.


John Cebasek
email@hidden
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