Experimental Physics and
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On 12/21/07 2:15 PM, Mark Rivers wrote: > That is the good news. The bad news is that setting the permissions > on that device, /dev/bus/usb/005/018 does not allow a non-privileged > user to access the device. In order for a non-privileged use to > access the device, I find that I need to set the permissions to 666 > on /proc/bus/usb/005/018 i.e. the /proc filesystem, not the /dev > filesystem. If I change the permissions on the /proc filesystem > manually then I can run the IOC in a non-privileged account. > > I am not a Linux expert by any means. What is the difference between > the /dev and /proc filesystems? Peter also mentioned the /sys file > system. How is that related? > > I am using the libusb library to access the device. With that API one > simply calls usb_find_busses and usb_find_devices to locate the device > you are interested in. You don't specify the file system anywhere. > > Any ideas how to get the permissions I need set on the device? > > Thanks, Mark Hi, Mark. Maybe the libusb library is using /proc/bus/usb as the virtual file system instead of /dev/bus/usb. What happens if you set the USB_DEVFS_PATH environment variable to "/dev/bus/usb" in the process environment of your IOC? -lewis
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ANJ, 02 Sep 2010 |
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