Hi, Am 26.02.2013 14:31, schrieb Xiaofan Chen: > On Tue, Feb 26, 2013 at 9:01 PM, Gert Franke <g.fra...@n-hands.de> wrote: >> After the standard device searching procedure and successfully opening >> one device, usb_claim_interface fails with rc=-3 "access denied". This >> is 100% reproducible. What does it mean and what can I do to avoid the >> problem? >> >> OS: Win 7 >> Lib: libusbx 1.0.14 >> Driver: libusb0.sys 1.2.5.0 (tested with libusb-win32) > > Take note libusbx support of libusb0.sys is quite > experimental with multiple issues. > So please try libusbx.git and try WinUSB or libusbk.sys > to see if that helps.
Thank you for your hints. In fact both steps were necessary: only changing to WinUSB brings up this issue https://github.com/libusbx/libusbx/issues/66 and only using the latest git version doesn't fix the problem. > If you want to use your existing libusb-win32 application > and the new libusbx program, then you should use > libusbk.sys. If possible, I would like to avoid deploying a new driver to our customers (USB performance is relevant only for a few of them). Therefore I would like to estimate if libusbx/libusb0.sys will become stable in the forseeable future (at least for our devices which are quite simple with respect to USB). Here are my debugging results (Win7/32, libusb0.sys, libusbx from git, file dates 2013-02-24): Within libusb_claim_interface and winusbx_claim_interface, in windows_usb.c #2693, a call to WinUSBX[1].Initialize() fails. This table entry has been filled in winusbx_init whith the address of WinUSB_Initialize() from WinUSB.dll. Why WinUSB? The code loads WinUSB whenever it is present and libusbK.dll is not. There are no specific methods for libusb0.sys. Does that mean that they are not yet implemented or that libusbK.dll is used to access libusb0.sys? Should I have this lib on my system? Thanks again, Gert ------------------------------------------------------------------------------ Everyone hates slow websites. So do we. Make your web apps faster with AppDynamics Download AppDynamics Lite for free today: http://p.sf.net/sfu/appdyn_d2d_feb _______________________________________________ libusbx-devel mailing list libusbx-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/libusbx-devel
