Sysfs is a Linux filesystem, normally mounted on /sys, which provides information about hardware and kernel components.

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Will sysfs replace procfs in the furture?

As I know, procfs has been old and chaotic, so sysfs was invented to resolve the problem. Will sysfs replace procfs in the furture? Or, sysfs will just replace part of the functions of procfs, such ...
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Difference between /dev and /sys

Exactly what is the difference between devfs and sysfs? Both seem to maintain a list of hardwares attached to the system. Then why the need for 2 separate fs even arose? As far as I can get /sys ...
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Allow non-root user go get network traffic statistics

I know that I can use cat /sys/class/net/eth0/statistics/rx_bytes to see the amount of received bytes. Sadly I only can run this command as root. When I am another user, I get cat: ...
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Is it possible to get network interface index not via /sys?

So what I'm looking for is an interface index (or name) but the real one. if_nametoindex(3) and ioctl(2) don't seem to help me here. Now the only way I found how to do this is via /sys. Let me ...
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Getting information from sysfs

I'm creating a script for polling information about network interfaces. For this I get some data from /sysfs. Everything went fine until I wanted to clarify all possible states of an interface (Which ...
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How do I know what decompression algorithms are compiled-in into the linux kernel?

If /proc/config.gz is unavailable, how do I know what decompression algorithms the running kernel is capable of using on a compressed cpio initramfs? Is the gzip algorithm always available, even when ...
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How do I find out what filesystem drivers are compiled-in into the linux kernel?

On a running linux system, what is a portable (among linux distributions) way to find out what filesystems the current kernel has compiled-in (not through modules) support for? Consider for example ...
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Best Practices for Configuring/Reading Sensor Devices

I have a gadget with a number of environmental sensors attached via an I2C bus, and would like to be able configure and read these sensors via an unprivileged application. Unfortunately, there ...
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Accessing GPIO after kernel boots

my rootfs.cpio has only following files: [root@localhost extract]# ls dev init tmp dev has console only. init is cross-compiled from the program given at the end: Then I make a my image and ...
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USB modalias. Meaning of numeric values

For the USB modaliases, I know that the values corresponding to the device's vendor and product ids can be found here: http://www.linux-usb.org/usb.ids Which online resources and/or kernel source ...
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Difference between /dev and /sys/class?

What is the difference between the device representation in /dev between the one in /sys/class? Is one prefered over the other? Is there something one offers and the other doesn't?
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Best way to implement a system configuration driver for Linux

Is there a standard architecture for a driver that allows to read an set system configuration for an embedded Linux system? System configuration means for example hardware calibration values, revision ...
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Unable to write to a GPIO pin despite file permissions on /sys/class/gpio/gpio18/value

This is on a Raspberry Pi. Here's the output of sudo ls -lL /sys/class/gpio/gpio18: -rwxrwx--- 1 root gpio 4096 Mar 8 10:50 active_low -rwxrwx--- 1 root gpio 4096 Mar 8 10:52 ...
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/sys/class filesystem on Linux

On Linux (Ubuntu 11.10 on a ARM processor in my case) I was looking for a way to measure CPU temperature. I found out that a cat /sys/class/thermal/thermal_zone0/temp did the trick. Now I wonder: ...
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How to find out easily whether a block device (or a part of it) is mounted somehow

I want to know what the easiest way is to determine (without root privilege) whether a block device (say sdb) or any part of it is mounted (and which part of it). Checking /proc/mounts for sdb is not ...
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Kernel recognizes USB device but then I can't find it in /sys or /dev

When I connect my Samsung 390G (a cheap cell phone!) to Ubuntu 13.04, dmesg seems to indicate that the storage device thereon is recognizable: [Sun Dec 29 01:26:10 2013] scsi16 : usb-storage ...
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Kernel module parameters vs /sys/class/… explanation

I was making (my first) kernel module to play with the gpio pins of my pandaboard and interrupts. Already "built-in", I noticed you can do (briefly) cd /sys/class/gpio echo 138 > export # a file ...
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Which of proc, sys etc. should be bind-mounted (or not) when chrooting into a “replacement” distribution?

This answer to another question basically boils down to chrooting into another Linux distribution in order to mainly use that as a replacement to its too restricted (but irreplaceable) parent. The ...
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Finding a char device in /sys using a Bash script?

I have one of these and I am trying to write a Bash script for finding the device path in /sys. My approach goes something like this: start in /sys/modules/usbled since this is the name of the ...
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Using Bash to write to a device in /sys?

I have one of these: Basically, it's a USB device with three LEDs (red, green, and blue). The Linux kernel has supported this device through the usbled module for quite some time now. However, I ...
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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 ...
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CONFIG_GPIO_SYSFS makes /sys/class/leds disappear

I have an embedded Linux board I'm working on, with a button and a couple LEDs. By default, I can control the LEDs via /sys/class/leds/redled/brightness However, I have no way to monitor the ...
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Why does rsync fail to copy files from /sys in Linux?

I have a bash script which uses rsync to backup files in Archlinux. I noticed that rsync failed to copy a file from /sys, while cp worked just fine: # rsync /sys/class/net/enp3s1/address /tmp ...
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How to retrieve sysfs devpath of a USB flash drive given its corresponding partition sysfs path?

I have a USB flash drive connected to a hub. Its storage device partition devpath in sysfs is /devices/pci0000:00/0000:00:12.2/usb6/6-1/6-1.2/6-1.2:1.0/host10/target10:0:0/10:0:0:0/block/sdb/sdb1. I ...
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Is there a generic approach to automatically make some sysfs controls ch{own,mod} user-accessible?

My current primary question motivator: $ ls -l /sys/devices/platform/samsung total 0 -rw-r--r-- 1 root root 4096 27. jaan 14:17 battery_life_extender drwxr-xr-x 3 root root 0 19. jaan 18:40 leds ...
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How does systemd-tmpfiles work?

I'm trying to change the value of /sys/bus/usb/devices/4-3/power/wakeup at every boot (4-3 according to my lsusb, it's the keyboard ID). The default value is: # cat ...
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Settings value in /sys/devices/platform/i8042/serio1/serio2/speed as no effect

I'm following this tutorial to ajust the TrackPoint speed for my Lenovo T420. However, setting a value in /sys/devices/platform/i8042/serio1/serio2/speed has no effect. The trackpoint is unaffected ...
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How do I learn what I can do with /proc and /sys

I'd like to know more about the advanced uses of the /proc and /sys virtual filesystems, but I don't know where to begin. Can anyone suggest any good sources to learn from? Also, since I think sys has ...