devices refers to questions about the Unix/Linux device special files, normally these are under /dev. Do not use this tag for physical devices (for that use e.g. usb or pci).

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7
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1answer
1k views

USB connect/disconnect notification

I use Linux Mint 13 MATE, and I'm trying to set up notifications when I plug/unplug devices. First of all, I found udev-notify package, but unfortunately it almost doesn't work for me: it works for ...
0
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0answers
16 views

Device nodes for an ATSC tuner not created

I'm trying to use an external tuner to tune to ATSC signals. But when I plug in the USB-Tuner I could see only frontend created. $ ls -ld /dev/dvb/adapter*{,/*} drwxr-xr-x 2 root root 60 Dec 5 ...
3
votes
0answers
62 views

Remote Mouse netcat (/dev/input/mice)

I was playing around with nc and I'm discovering how powerful and versatile this tool is. I was wondering how the file /dev/input/mice works because when I do cat /dev/input/mice you see the output, ...
2
votes
1answer
108 views

chroot with unionfs-fuse, can't access /dev/*

I have created the a chroot jail in combination with unionfs-fuse so that I don't need to install another system inside it. However, the resulting system's /dev entries are not readable.This is ...
5
votes
2answers
1k views

How can I create a direct 8khz audio pipe in Ubuntu?

I'm interested in creating musical programs like these: http://www.youtube.com/watch?v=GtQdIYUtAHg&feature=player_embedded Essentially these programs just generate sequences of integers, which ...
4
votes
1answer
62 views

Do all devices under Linux have a device node?

I know that each device on Linux is either a char or block or network device. Do all physical devices that exist on Linux have a device node under the /dev directory? I'm not talking here about ...
0
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1answer
25 views

Does network interface device have device inodes [duplicate]

Does network devices have device nodes because i have looked inside /dev directory and have not found any corresponding device node although it's up and running
15
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3answers
6k views

Understanding /dev and its subdirs and files

$ ls -l /dev/stdin /dev/fd/0 lrwx------ 1 tim tim 64 2011-08-07 09:53 /dev/fd/0 -> /dev/pts/2 lrwxrwxrwx 1 root root 15 2011-08-06 08:14 /dev/stdin -> /proc/self/fd/0 $ ls -l /dev/pts/2 ...
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0answers
17 views

give group permissions to specific device

I have a panning web camera I built, (future robot arm). The camera pans via a web interface (cgi scripts and JS interface) which access an arduino. To enable sending of commands via the interface, I ...
2
votes
1answer
34 views

who is accessing /dev/video0

I have a streaming video feed set up with the motion package. something like this: https://www.youtube.com/watch?v=jGkHSU-UPLU works Great. What I want to know, is who is connecting to my streaming ...
11
votes
3answers
971 views

Are there alternatives to using `udev`?

While I understand the greatness of udev and appreciate the developers' effort, I was simply wondering if there is an alternative to it. For instance, I might imagine there should be a way to make ...
3
votes
1answer
294 views

Trying to read USB Audio Device, but /dev/hidraw0 is unavailable for reading

I'm trying to write a simple driver for my USB Sound Card (just for fun) on Xubuntu 14.04 -- for example, I want to have an opportunity to control volume on my laptop via this device. The problem is ...
2
votes
0answers
42 views

Capturing data from a Fluke 1620a via Bash /dev/tcp file descriptor

I am currently trying to develop a script that will connect to a Fluke DewK 1620a Themo-Hygrometer and pull the current temperature and humidity readings from the device. While these devices have a ...
2
votes
0answers
33 views

Is there support for flattened device tree in Sparc 32 port of the Linux kernel?

We are trying to write a minimal bootloader for booting the linux kernel on a Sparc V8 processor simulator. From what I understand, the interface between the bootloader and kernel consists of a data ...
0
votes
1answer
32 views

Can't Make a LDD for a Devkit8000

I'm trying to build a Linux Device Driver for a Devkit 8000. I'm getting the following errormessage: When I try to follow it's directions I get asked a bunch of yes/no questions I don't really ...
4
votes
2answers
46 views

How to run an application with certain group permissions?

I have a 3D printer, with which my PC can communicate through /dev/ttyACM0: crw-rw---- 1 root uucp 166, 0 16 nov 14:58 ttyACM0 The 3D printing application repetierHost requires read/write access ...
2
votes
1answer
93 views

create several /dev/xconsole files automatically upon boot

I understand from my previous question that the /dev/xconsole file can be created using mkfifo. On my system (Debian Wheezy), /dev/xconsole gets created automatically. I am wondering who creates it ...
2
votes
1answer
439 views

Is it possible to simulate/force/fake an USB device unplug and replug on Linux?

So I've got a strange problem that I've been running onto. I've got a bitcoin usb miner, Bitfury, and I'm using CGMiner to mine. When I start the application, as root, the USB device is not detected ...
2
votes
1answer
326 views

How to get device filename from lsusb output or by device path

Related question: USB connect/disconnect notification When the device is plugged/unplugged, I get instant notification, that's great. But to make it (almost) perfect, I also want to get device ...
5
votes
1answer
1k views

How to be notified when a USB device was plugged in?

My system has to auto-mount USB devices; how can I be notified when a USB device is plugged in? Where can I read more about this subject? I would like to handle this problem via C or a shell script. ...
3
votes
0answers
143 views

Why does a device show up as hidraw instead of hiddev?

I read the kernel documentation for hidraw and hiddev, and I understand the differences, but I am wondering how the kernel decides whether or not a device should show up as /dev/hidraw* or ...
3
votes
1answer
121 views

How to disable USB devices based on their vendor ID on GNU/Linux?

In that question someone wanted a blacklist for all USB devices, and then only allow specific devices. In this question, we want to accept all USB devices, but prevent the driver (e.g. cdc_acm) from ...
4
votes
2answers
4k views

How to grant non-root user access to device files

I have device file that appears in /dev when a specific board is plugged in. The read and write operations to it work just fine, but in order to open the device file the program needs to be executed ...
2
votes
0answers
29 views

PC speaker device missing

I've just connected a small internal PC speaker to my motherboard. The beep command is producing sounds correctly. The pcspkr is loaded but there is no /dev/pcsp, so I cannot send audio to it. How ...
68
votes
12answers
227k views

How do I find out what hard disks are in the system?

I need to know what hard disks are available, including ones that aren't mounted and possibly aren't formatted. I can't find them in dmesg or /var/log/messages (too much to scroll through). I'm hoping ...
1
vote
1answer
56 views

talk to modbus device

I currently have a minimal install of Red Hat 6.5 running, on the machine I need to talk to a modbus device. I am wondering what tools and drivers are needed on a linux machine to talk to a modbus ...
3
votes
0answers
63 views

Bad/strange USB device issue: failed to shutdown/restart

On a fresh Arch Linux installation with Intel i7 processor and an Nvidia graphics card, I noticed during boot log messages related to a usb device filled the screen before it reached the graphical ...
3
votes
1answer
3k views

How do I find out which process is using my V4L2 webcam?

I tried to run the following: $ vlc -I dummy v4l2:///dev/video0 --video-filter scene --no-audio --scene-path webcam.png --scene-prefix image_prefix --scene-format png vlc://quit --run-time=1 ...
6
votes
2answers
770 views

What happens if I run fsck on /dev/sda instead of /dev/sda1?

When I have run fsck in the past I have always run it on what I thought was a filesystem partition, ie. fsck -yf /dev/sdaN, where N is the partition number on disk A. A friend of mine recently ran ...
1
vote
0answers
60 views

How/where are linux device capabilities / bitfields set?

I have a device that has this output in /proc/bus/input/devices: I: Bus=0003 Vendor=05b8 Product=3280 Version=0111 N: Name="PixArt USB Optical Mouse" P: Phys=usb-0000:00:1a.0-1.1/input0 S: ...
0
votes
0answers
144 views

How can I mount the Logitech C270 in the zynq-7000 (with Linaro linux)?

I am doing camera control programming for a university project using zynq 7000. I want to mount the camera module that's for the Logitech C270 (like this ...
1
vote
1answer
110 views

create several /dev/xconsole files

I am using /dev/xconsole to send system logs from rsyslog. That works great, because I am don't have to store the logs on disk. I would like to have another similar file , i.e /dev/xconsole1 where I ...
1
vote
0answers
34 views

How do you determine the capabilities of a WebCam?

I have a collection of WebCam's lying around. Some of them are new, some go back a decade (gotta love not having to "upgrade" devices in Linux :). Somehow I've developed the impression that ...
3
votes
1answer
332 views

cannot create special file /dev/pts/0

When using midnight commander in console, I cannot "toggle" the window (using CTRL-o Not an xterm or Linux console; the panels cannot be toggled however, my $TERM is set to linux. After some ...
1
vote
0answers
16 views

character device file (rtai_shm) disappears under runlevel=5 in fedora9 (exists when runlevel=3)

I am trying to run Realtime (RTAI) on my Linux Fedora 9 machine. For that, it is needed to have a character device file, named rtai_shm, in /dev, that takes care of shared memory. I have made this ...
3
votes
3answers
622 views

Why doesn't xsetwacom work from udev?

I made a script to rotate my Wacom Bamboo tablet 180 degrees. It works fine when I execute it as myself (user) or root, but when started from udev (i.e. when plugging the tablet into a usb port) it ...
0
votes
0answers
49 views

unitek nec upd720200 not detected

I've decided to buy an USB3.0 controller on PCI for my debian machine. I did a short research and it appeared that NEC chips will be fine. I've bought Unitek NEC UPD720200 and I does not work: I ...
0
votes
1answer
56 views

Determine driver for network interface [duplicate]

I wanted to see which driver was associated with some of the network interfaces listed by ip link. My first thought was to find the network interfaces in /dev and look at the device major and minor ...
1
vote
1answer
104 views

USB 3G dongle internet keeps failing on Fedora 20 laptop

I use a 3G dongle for internet in my summerhouse, it has worked fine all summer, but since yesterday it has been losing connection, or something and I have to unplug it and insert it again for the ...
4
votes
1answer
1k views

can not create /dev/shm

I need to create /dev/shm on an embedded ARM system. From "Installed The Latest Changes to Current and......". I see that it can be created with mkdir /lib/udev/devices/shm, but I'm wondering what ...
1
vote
1answer
130 views

How do I send RTSP video to a program that reads from a character device?

I have an IP-CAM that streams video over RTSP and I want to detect bar codes from it with zbarcam (from Ubuntu's zbar-tools package). According zbarcam's manual, it expects to be given a video4linux ...
1
vote
3answers
78 views

Looking at the content of a character device's file [duplicate]

Why is it possible to look at the contents of a block device's file like /dev/sda using cat or a hex editor? Why can I not do the same for a character device like /dev/pts/3?
2
votes
1answer
473 views

udev Unable to Rename Network Device: Device or Resource Busy

I'm trying to use udev rules in order to give my network interfaces static, consistent names. However, it seems like there is some race condition happening preventing these rules from consistently ...
3
votes
3answers
272 views

equivalent of `grep -a /dev/sda1` on Darwin?

I want to run something like % sudo grep -i -a 'some-string' <drive device> On Linux, <drive device> would be something like /dev/sda1. How can I find the equivalent on Darwin? (In ...
3
votes
2answers
119 views

Transfering content of block devices

For the purpose of backups, I'd like to transfer (several) whole disk partitions over an ssh link. So the source is a block special device, and the target should be a regular file. Common tools seem ...
4
votes
1answer
412 views

look up the device from its tty file?

Here is from my Ubuntu $ ls /dev/*tty* /dev/tty /dev/tty17 /dev/tty26 /dev/tty35 /dev/tty44 /dev/tty53 /dev/tty62 /dev/ttyS12 /dev/ttyS21 /dev/ttyS30 /dev/tty0 /dev/tty18 /dev/tty27 ...
2
votes
0answers
187 views

/dev/sda not appearing after secure erase

I decided to wipe my SSD with a secure erase before installing Arch Linux, since the Arch wiki said that it would improve performance. I followed the instructions listed on the wiki, but now when I ...
6
votes
2answers
1k views

What’s the difference between a “raw” and a “cooked” device driver?

Does this concept only apply to terminal drivers (which is what most sites cover) or to any driver in general?
2
votes
1answer
2k views

Map physical USB device path to the Bus/Device number returned by lsusb

I need to get the title of the attached USB device. I can do that with lsusb. udev allows some substitutions when I write rules: say, we can use $kernel to get name of the device, or $devpath to get ...
2
votes
1answer
29 views

PCI header in my laptop looks different from free-electrons' PCI header

I'm trying to develope a pci driver but I can not compile it because my pci header is quite different from books and references. My distribution is 3.15.7-1-ARCH. ...