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3
votes
3answers
6k views

GSM modem does not create /dev/ttyUSB file

I installed Kannel in a server, and I want to use a GSM 3G USB modem to send/receive SMS messages, as described in section SMS Centers > GSM Modem of the Kannel User Guide. I have already installed, ...
1
vote
1answer
111 views

Difference between Device file and device drivers

I am beginner in device driver programming. I don't get the difference between device drivers and device files in Linux. Can anyone explain the difference?
0
votes
0answers
148 views

What are high level and low level device drivers

Recently I read that there are two types of drivers (at least for disk), one that are called high level drivers and another called low level device drivers. Can some one tell me what these are, and ...
4
votes
2answers
302 views

How to take sha-1, sha-256 or MD5 of CDs / DVDs?

I just tried burning both a Debian CD and a Debian DVD from their .iso files and I've got a weird behavior: the checksum of the CD is correct but the one of the DVD ain't. Here's what working: ...
3
votes
5answers
2k views

GNU/Linux (Debian): detecting hard-disks mappings?

Let's suppose you have two hard-disks: one internal (boots GNU/Linux); one external (USB). "fdisk -l" detects both, but will not tell you which is /dev/sda and which is /dev/sdb. "lsusb" will tell ...
1
vote
1answer
66 views

2 or more programs in same USB serial converter

Having a network of lets say 10 devices in RS-485, connected to the linux PC with a RS-485 to USB Converter. Already there is a C program interacting with the serial converter at /dev/ttyUSB0. My ...
1
vote
0answers
52 views

Which Unixes support cross-device filesystem links (in particular for rename)?

Just read the following on the FreeBSD man page for the rename syscall: ... [EXDEV] The link named by to and the file named by from are on different logical devices (file systems). Note that ...
4
votes
2answers
102 views

Can you identify transport via sysfs?

I'm writing a script, and I'm interested in being able to identify the transport class (fc - "fibre channel", scsi, iscsi, etc.) for a given block device. I can retrieve this information via ls -l ...
1
vote
0answers
277 views

Debian Wheezy USB2 ehci_hcd

I have a friend who decided to switch to Linux from Windows. I was helping her to get up and running as quickly as possible but we ran into a problem which I can't seem to solve. She uses Debian ...
3
votes
2answers
117 views

Permissions to print directly to USB printer

I've a netbook with Linux. I've a usb/serial printer and I added the line chmod 666 /dev/tty* to rc.local and it prints straight after a reboot. When I close the lid of a netbook for a while and then ...
6
votes
2answers
3k views

How does cat know the baud rate of the serial port?

I regularly use cat to view debugging information in the console from my FPGA development board over the serial connection, but I never have had to tell linux what the baud rate is. How does cat know ...
1
vote
1answer
178 views

A drive changes device file name after resuming from suspend (Linux Mint 14)

I'm running into a very odd problem: When I resume Mint 14 from suspend, one of my drives (/dev/sdc) changes letter / device file name (to /dev/sdd). fdisk -l shows that it has the same partitions, ...
2
votes
0answers
68 views

How to rename devices for graphical output such as VGA0

On my Laptop the names of my graphical outputs change depending on what chip is activated in the BIOS. This leads to problems in some scripts where outputs such as VGA-0 or LVDS-0 are specified. So I ...
3
votes
2answers
662 views

Can I stop Linux from listening to a USB input device as a keyboard, but still capture events with a program?

I have a USB barcode scanner at /dev/input/event0 (/dev/input/by-id/usb-Metrologic_Metrologic_Scanner-event-kbd), and scanning a barcode causes it to send keypress events. I'm capturing these ...
0
votes
2answers
97 views

ECC on a single block device

I have an SSD that I suspect failing silently now and then. I have run badblocks on it and it is clear that it is not bad sectors but might instead be some race condition in the electronics, in which ...
0
votes
1answer
73 views

Random bug in Linux

Some time ago, I remember reading an article on randomization in computing, and how random you can actually get a system to be. The article came about, if I'm not mistaken, because of some seemingly ...
1
vote
0answers
177 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 ...
0
votes
2answers
86 views

IO utilization for /dev/null redirection?

I always use nohup to start my system. However, the output to nohup is so big that I'm thinking to redirect it to /dev/null. My concern is, will redirecting to /dev/null also incur some I/O operations ...
2
votes
1answer
89 views

GPS Device Attached to Linux Mint 15

I purchased a Silvercrest GPS device from Lidl recently, but the software that came with it is a tad "underpowered" to say the very least and has no Linux support. I'm attempting to get at the raw ...
1
vote
1answer
465 views

Beaglebone Black Device Tree for LCD4 cape

The device tree for LCD4 cape is located at /lib/firmware/BB-BONE-LCD4-01-00A1.dts When I looked into it, the declaration of those GPIO buttons confuse me. There are five buttons according to ...
1
vote
1answer
411 views

“Permission denied” when writing to /dev/stdout

Why cannot I write to /dev/stdout? I am logged in as the root user, what greater permission could I have? root@ubuntu:/# tcpdump -i 2 -w /dev/stdout tcpdump: /dev/stdout: Permission denied The ...
2
votes
1answer
319 views

ffmpeg webcam to device driver , output 8 bit grayscale

With the following command i'm trying to capture 10fps and send them the device driver. Now i want 8 bit gray raw frames (640x480= 307200 bytes per frame) to be send to the device driver. I can't ...
3
votes
2answers
957 views

/dev/hidraw: read permissions

What do I need to do to have read permissions on /dev/hidraw*? I'm seeing stuff about udev rules and saw this on the net, but the world of udev is like a foreign land to me, and if there's some sort ...
7
votes
4answers
6k views

Find out what device /dev/root represents in Linux?

On linux, there is a /dev/root device node. This will be the same block device as another device node, like /dev/sdaX. How can I resolve /dev/root to the 'real' device node in this situation, so ...
1
vote
0answers
81 views

Any good usb-serial (RS485) adapter to use with GNU/Linux?

I'm having problem with usb-serial (RS485) adapters. Firstly, I tried ch341 without success. The problem in this case is the linux driver, made by reverse engeneering (sadly without any help from the ...
2
votes
2answers
896 views

What is a device controller, and where does it fit in between the kernel and the device?

Can someone please explain the concept of a device controller (hard disc controller, NEC PD765 compatible controller etc.). Here are some definition of key terms which might be needed for the ...
1
vote
1answer
193 views

dd outputting: “function not implemented” when trying to write to /dev/sg11

I'm trying to use the following command: dd if=/dev/urandom of=/dev/sg11 bs=16K count=1 But when executing it, I get the following error: dd: writing `/dev/sg11': Function not implemented When I ...
4
votes
2answers
751 views

Why are there so many virtual terminal devices?

I've been reading the Advanced Linux Programming book and it mentions about virtual terminals which, if I understood it correctly, it is a Linux-specific feature (not in Unix) to allow multiple login ...
1
vote
1answer
69 views

Need list of HDD devices excluding my os HDD

I want list out whole HDD device excluding my os running device attached to my system. I did lot's of googling and fired many more commands in command line of linux. but can't gating proper output. ...
3
votes
1answer
211 views

How to get the actual keyboard device given the output of /proc/bus/input/devices?

When I run: cat /proc/bus/input/devices ...I receive the following output: ... I: Bus=0003 Vendor=040b Product=2000 Version=0110 N: Name="Generic USB Keyboard" P: Phys=usb-0000:00:1d.0-1/input0 ...
1
vote
2answers
162 views

Meaning of “target” in virsh XML VM definitions.

I recently found that the target=hda tag in virsh was actually not translating into guest OS (guest OS's use /dev/sdX as the disk device names, in general, it seems). virt-install and /dev/hda vs. ...
1
vote
2answers
388 views

virt-install and /dev/hda vs. /dev/sda

It appears that my virt-install xml file (i.e. created when defining a VM) specifies targets "hda", "hdb", and so on as the devices for disks, however, the VM, once created, lists /dev/sda, /dev/sdb, ...
3
votes
1answer
226 views

Why are devd rules applied before devfs rules?

My problem I have the following lines in /etc/devd.conf which execute the usbhidaction for a /dev/uhid* device with the named vendor and product id. attach 100 { match "vendor" "0x046a"; ...
3
votes
2answers
964 views

Creating eth0 with consistent network device naming

From my understanding, Arch Linux uses Consistent Network Device Naming where the network devices are no longer named eth0, eth1, etc. I use the proprietary MATLAB software which requires a device ...
3
votes
1answer
334 views

Find out if a specific device is an USB mass storage

Context I'm automating SD card imaging from an existing dd factory image. The SD card is always connected through an external USB card reader and thus appears in the system as a SCSI block device ...
0
votes
2answers
528 views

Cheap 100% Debian compatible ultrabooks [closed]

I'm looking for relatively cheap ultrabooks with 100% Debian compatible features. I have several ultrabooks on my list but they contain some additional features which i don't need (additional ...
2
votes
1answer
647 views

“PS/2 Generic Mouse” gets lost. How to reload without reboot?

I am running Ubuntu 12.04LTS on a ThinkPad E420s. My Trackpoint is recognized as "PS/2 Generic Mouse". My problem is that it doesn't load/disappears after booting or after suspension. I can't move ...
1
vote
0answers
263 views

Check if Keyboard and Mouse are plugged in

Is there a way to detect if a keyboard and a mouse is plugged in (and working) in Linux? This will be embedded in a PXE setup, so I only have Kernel + Modules and Busybox available. Bonus question: ...
8
votes
4answers
4k views

If I connect a physical device, how can I ever know which device file belongs to it?

Say I plug in several USB drives which don't get automatically mounted. How can I find out which device file belongs to which physical device, so I can mount it for example? I'm running Mac OS X but ...
4
votes
2answers
200 views

Can I query which processes (if any) are currently accessing the microphone?

I'm running Debian (technically Raspbian), trying to get a Star-Trek style voice-command system. I've got it mostly up and running, but in the interests of privacy and all that jazz, I don't want my ...
2
votes
1answer
51 views

Assigning static device path

I have 4 flash cards plugged in, sequentially named by system: /dev/sda1 /dev/sdb1 /dev/sdc1 /dev/sdd1 I want to assign static pathes to them, so every time the system boots up their pathes will ...
1
vote
2answers
124 views

/dev/console points to tty0?

I've been trying to understand the /dev/console device, but there are a few things I'm not clear on: What is the purpose of this device? From what I can gather it's just a place for the kernel to ...
2
votes
1answer
190 views

open() console for default file descriptors

I'm reading a shell program implementation in C ( the xv6 shell from MIT's 6.828 Operating System Engineering course ). The main() function for this shell starts with the following code: //Assumes ...
-1
votes
1answer
161 views

what type of device drivers are available in linux [closed]

The different types of device drivers used in linux are character device and block device. Is there another classification?
2
votes
2answers
151 views

Detecting the device of a crypto mount

I have an external eSATA-hdd on an OpenSUSE 12.2 system. The external hdd has an LVM on a dm-crypt partition. I mount it by powering it up and then doing rescan-scsi-bus.sh cryptsetup -v luksOpen ...
5
votes
1answer
2k views

using devtmpfs for /dev

I have noticed the following option in the kernel: CONFIG_DEVTMPFS Device Drivers -> Generic Driver Options -> Maintain devtmpfs to mount at /dev And I see that it is enabled by default in ...
1
vote
1answer
1k views

pvcreate error on partition

I can't create this partition, I'm getting this error shown below: Device /dev/mapper/vg_paperino-lv_rootp1 not found (or ignored by filtering) Below are the steps that I'm doing on CentOS: ...
1
vote
1answer
158 views

Creating a terminal device for interprocess communication

I'd like to know how to create a terminal device to simulate a piece of hardware connected through a serial port. Basically, tty device with a certain baud rate that can be read from and written to ...
3
votes
3answers
539 views

Special File that causes I/O error

I want to automatically test if a piece of software reacts as expected if an essential SQLite DB file fails to be read (causing an I/O error). Exactly that happened some days ago at a client. We ...
1
vote
1answer
355 views

Installing a platform driver

I have recently acquired a device driver for an integrated watchdog timer on a x86 board on which I am running a minimal Linux system. The kernel is 3.6.11 and it has been built using buildroot. My ...