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1

If /dev/video1 exists, it is probably attached to something. Try pulling the second camera out of the hub, wait a few seconds, and ls /dev | grep video -- the node should disappear. Likewise, when you plug it in, it should appear. This would clarify whether or not it is using that node.


0

Linux What you've posted is a snippet of C code. (And not even a working one.) It isn't going to work at a shell prompt. There is no shell interface to ioctl, but you can use Perl. #!/usr/bin/perl require "sys/ioctl.ph"; if (@ARGV) { $ioctl = 0x4b32; # KDSETLED $ARGV[0] =~ /^[0-8]+$/ or die "$0: $ARGV[0]: invalid argument"; $arg = ...


2

That C code would not work anyway -- fdopen() requires more than one argument and returns a file stream, not a file descriptor. I can remember doing this a few years ago, I thought via Xlib, but I could not find my old code (occasionally the collection gets purged) but I figured someone must have a simple app for this on github or something. Low and ...


5

Your problem is that you try to enter C code into a shell prompt, this doesn't work for obvious reasons. You could either put it into a correct C file, compile it and get a valid binary you could execute: #include <linux/kd.h> #include <sys/ioctl.h> #include <fcntl.h> #include <unistd.h> #include <err.h> #include ...


3

USB 2.0 or 3.0 is a hardware specification and has little to do with the OS. There's no way to downgrade (or upgrade) an specific USB version. What you can do is plugging your device in a 2.0 hub. USB 3.0 is totally backwards compatible with 2.0 and 1.1 devices, but some glichs can appear in the kernel implementation of the specification, in such cases is ...


0

On OpenBSD audio playback/muxing is handled by the sndiod(1) daemon. Changing the default playback devices is confusing because the list of valid devices does not appear to be documented. Add the following to /etc/rc.conf.local sndiod_flags="-f sun:1" Then run sudo /etc/rc.d/sndiod restart


0

I was eventually able to solve this by adding the following command to one of my startup scripts: klogconsole -l 3 This seems to make the system shut up. (At least, after the point where the command is executed.)


1

If Miroslav Koskar's suggestion regarding kernel loglevel did not help (you might as well use 2 or 1 there instead of 3, IMO), have a look in your /etc/syslog.conf (or rsyslog.conf) for a line containing /dev/console. This indicates the level of messages that are passed to the console by the system logger, which maybe the case if the kernel isn't doing it ...


3

Boot with: quiet loglevel=3 For info: quiet [KNL] Disable most log messages loglevel= All Kernel Messages with a loglevel smaller than the console loglevel will be printed to the console. It can also be changed with klogd or other programs. The loglevels are defined as follows: 0 (KERN_EMERG) system is ...


1

If the messages have numbers before them, these are messages produced by the Linux Kernel. (The number means the number of seconds since the system was booted up.) To stop these messages, add the quiet parameter to your kernel command line. You may do this by editing a file in the /boot partition or using a configuration tool provided by your bootloader, ...


9

I think you can use UDEV to do what you want. Creating a rules file such as/etc/udev/rules.d/99-thumbdrives.rules you'd simply add a rule that will allow either a Unix group or user access to arbitrary USB thumb drives. KERNEL=="sd*", SUBSYSTEM=="block", ENV{DEVTYPE}=="disk", OWNER="<user>", GROUP="<group>", MODE="0660" Would create the device ...


0

Just found the answer myself. It appears that http://www.linux-usb.org/usb.ids also contains the meaning for the device/interface classes, subclasses and protocols. They are almost at the end of the file. Search it for "List of known device classes, subclasses and protocols" string. So in my case: ic:isc:ip (which is 02:02:01) means a communication device, ...


0

Real D'Oh moment here The problem was Numlock. The solution was: System Settings -> Keyboard -> Layout settings -> Options -> Miscellaneous compatibility options I checked Numeric keypad keys always enter digits (as in Mac OS) And now things work as I expected


0

You are missing with usb_register and probe functions Here is updated device driver with usb_register and probe functions #include <linux/module.h> #include <linux/kernel.h> #include <linux/usb.h> #include <linux/usb/input.h> #include <linux/hid.h> MODULE_LICENSE("GPL"); MODULE_AUTHOR("Aruna Hewapathirane"); ...


1

Magic numbers (or in this case, identifiers) are most of the time random, through sometimes funny (think hexadecimal DEADBEEF). These numbers could or couldn't be incidental, but there's no reason why they would want to be "close anagram" of anything. I would brush off as mere coincidence.


0

As you are going to sell it, I guess you don't need the data in here. You can then run the Windows installer from the ISO you have, delete all existing partitions and install Windows with the partitions of your choice. If you are not confortable with Windows partition manager, you could also delete everything from a live CD of Linux.


0

Unload your USB HCI kernel modules (anything *hci_hcd and *usb*) and reload them. This is the only reliable way to actually cut the power to the USB ports. There are other less severe method to achieve the same thing, but they are not guaranteed to work depending on how your device fails.


0

Well, I've got an answer to #2, found over at the Ubuntu stack exchange: sudo sh -c "echo 0 > /sys/bus/usb/devices/<devId>/authorized" sudo sh -c "echo 1 > /sys/bus/usb/devices/<devId>/authorized" where devId can be figured out (in my case, since I'll always know the exact expected product name) by inspecting ...


0

There's a decent thread on this here. USBMon's text interface is limited to 32 bytes, but the binary output will include everything, so you can use that. Wireshark is capable of understanding usbmon's binary format, as well as Virtual USB Analyzer, or you can write your own tool. I haven't actually tried it, but I have compared some small dumps taken with ...


1

The devices in /dev/bus/usb/XXX/YYY follow naming policies in the kernel as noted Gilles in the comments. XXX is the bus number which is quite stable, but YYY changes every time the USB device gets enumerated (when a device just got inserted or reset). This cannot be changed and you shouldn't have to change this either. If you need to change permissions on ...


0

The reason why this USB HID device works in Windows is because there may be specific drivers written for it, the reason why it works for GRUB is that the device operates in so-called boot mode. USB HID devices support two modes of operation, boot mode and HID mode. The former makes it possible to use the device in BIOS without having BIOS implement a full ...


0

I seem to recall that USB is a protocol that requires the computer to initiate the communication. It's not allowed to speak on its own. So the driver actually talks into the raw device and then captures the output. However, that's only a hunch, I'll also wait for another answer to confirm my suspitions.



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