Commands tagged kernel (37)

  • Gets the (previously obtainable with: finger @kernel.org ) info of the latest linux kernel versions available. Show Sample Output


    0
    curl 'https://www.kernel.org/kdist/finger_banner'
    Testuser_01 · 2012-03-04 21:10:19 5
  • Well, this is quite useful for testing if your hardware watchdog is working properly.


    0
    echo c > /proc/sysrq-trigger
    fangfufu · 2013-05-07 19:41:40 7
  • echo 1 > /proc/sys/sunrpc/nfs_debug && tail -f /var/log/messages to debug NFS issues.


    0
    echo 1 > /proc/sys/sunrpc/nfs_debug
    harpo · 2014-08-12 14:40:55 10
  • Get newest kernel version by parsing the most bleeding-edge Makefile possible. Useful for doing things like writing live ebuilds and/or self-updating PKGBUILDs for testing purposes. Breakdown: * wget -qO - https://raw.githubusercontent.com/torvalds/linux/master/Makefile — retrieve Makefile and pipe to stdout * head -n5 — only the first 5 lines are relevant, that's where all the version variables are grep -E '\ \=\ [0-9]{1,}' — version variables always have an equals sign followed by a number * cut -d' ' -f3 — extract the individual numbers from the version variables * tr '\n' '.' — replace newlines with periods * sed -e "s/\.$// — remove trailing period Show Sample Output


    0
    wget -qO - https://raw.githubusercontent.com/torvalds/linux/master/Makefile | head -n5 | grep -E '\ \=\ [0-9]{1,}' | cut -d' ' -f3 | tr '\n' '.' | sed -e "s/\.$//"
    realkstrawn93 · 2021-04-27 17:12:05 505
  • Kernel developers might need to know what indices to map to the IOAPIC if building a new kernel from scratch. This command gives users a guide to go off of.


    0
    cp /proc/interrupts irq-ref.txt
    realkstrawn93 · 2022-02-23 19:53:02 960
  • Whenever you compile a new kernel, there are always new modules. The best way to make sure you have the correct modules loaded when you boot is to add all your modules in the modules.autoload file (they will be commented) and uncomment all those modules you need. Also a good way to keep track of the available modules in your system. For other distros you may have to change the name of the file to /etc/modprobe.conf Show Sample Output


    -1
    find /lib/modules/`uname -r`/ -type f -iname '*.o' -or -iname '*.ko' |grep -i -o '[a-z0-9]*[-|_]*[0-9a-z]*\.ko$' |xargs -I {} echo '# {}' >>/etc/modules.autoload.d/kernel-2.6
    paragao · 2010-01-13 02:12:08 5
  • Disable randomisation address Show Sample Output


    -1
    echo 0 > /proc/sys/kernel/randomize_va_space
    gunslinger_ · 2010-07-11 16:42:42 5
  • Same as 7272 but that one was too dangerous so i added -P to prompt users to continue or cancel Note the double space: "...^ii␣␣linux-image-2..." Like 5813, but fixes two bugs: [1]This leaves the meta-packages 'linux-headers-generic' and 'linux-image-generic' alone so that automatic upgrades work correctly in the future. [2]Kernels newer than the currently running one are left alone (this can happen if you didn't reboot after installing a new kernel).


    -1
    sudo aptitude remove -P $(dpkg -l|awk '/^ii linux-image-2/{print $2}'|sed 's/linux-image-//'|awk -v v=`uname -r` 'v>$0'|sed 's/-generic//'|awk '{printf("linux-headers-%s\nlinux-headers-%s-generic\nlinux-image-%s-generic\n",$0,$0,$0)}')
    Bonster · 2011-04-25 05:19:57 4
  • Fetches latest stable release version from first entry between tags Show Sample Output


    -1
    curl -s -k https://www.kernel.org/feeds/kdist.xml | sed -n -e 's@.*<guid>\(.*\)</guid>.*@\1@p' | grep 'stable' | head -1 | awk -F , '{print $3}'
    Wafelijzer · 2013-12-17 23:59:27 8
  • The platform-agnostic version of https://www.commandlinefu.com/commands/view/25276/compute-newest-kernel-version-from-makefile-on-torvalds-git-repository because macOS doesn't have wget installed


    -1
    curl -s -o - https://raw.githubusercontent.com/torvalds/linux/master/Makefile | head -n5 | grep -E '\ \=\ [0-9]{1,}' | cut -d' ' -f3 | tr '\n' '.' | sed -e "s/\.$//"
    realkstrawn93 · 2023-08-10 22:25:55 230

  • -4
    aptitude purge linux-image | grep ^i | grep -v $(uname -r)
    lgallardo · 2010-06-11 22:20:42 8
  • Display the machine "hardware name" 32 or 64 bit. "x86_64" is shown on 64 bit machines "i686" is typically shown on 32 bit machines (although, you might also see "i386" or "i586" on older Linuxen). On other "unix-like" systems, other hardware names will be displayed. For example, on AIX, "uname -m" gives the "machine sequence number". For whatever reason, IBM decided that "uname -M" would give the machine type and model. (ref: http://www.ibm.com/developerworks/aix/library/au-aix-systemid.html ) On Sun Solaris, "uname -m" can be used to determine the chip type and "isainfo -v" will reveal if the kernel is 64 or 32 bit. (ref: http://www.ibiblio.org/pub/packages/solaris/sparc/html/32.and.64.bit.packages.html ) A more reliable way to determine "64-bit ness" across different Unix type systems is to compile the following simple C program: cat <<eeooff > bits.c /* * program bits.c * purpose Display "32" or "64" according to machine type * written January 2013 * reference http://www.unix.org/whitepapers/64bit.html */ /* hmm, curious that angle-brackets removed by commandlinefu.com data input processing? */ #include "/usr/include/stdio.h" long lv = 0xFFFFFFFF; main ( ) { printf("%2d\n",(lv < 0)?32:64); } eeooff Compile and run thusly: cc -o bits bits.c; ./bits Show Sample Output


    -4
    uname -m # display machine "hardware name"
    mpb · 2013-01-04 11:46:43 16
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Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

Google URL shortener
Use curl and sed to shorten an URL using goo.gl without any other api

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Hold off any screensavers/timeouts
Moves the mouse 1 pixel down and to the right, then immediately back again, every 4 minutes. This keeps screensavers from turning on. I have used this extensively and I've never even noticed the mouse movement because it is so subtle.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Reset hosed terminal,
stty sane resets the tty to basic usable function. The ^J is a newline -- sometimes CR/LF interpretation is broken so use the ^J explicitly.

Function that outputs dots every second until command completes
Very useful in shell scripts because you can run a task nicely in the background using job-control and output progress until it completes. Here's an example of how I use it in backup scripts to run gpg in the background to encrypt an archive file (which I create in this same way). $! is the process ID of the last run command, which is saved here as the variable PI, then sleeper is called with the process id of the gpg task (PI), and sleeper is also specified to output : instead of the default . every 3 seconds instead of the default 1. So a shorter version would be sleeper $!; The wait is also used here, though it may not be needed on your system. $ echo ">>> ENCRYPTING SQL BACKUP" $ gpg --output archive.tgz.asc --encrypt archive.tgz 1>/dev/null & $ PI=$!; sleeper $PI ":" 3; wait $PI && rm archive.tgz &>/dev/null Previously to get around the $! not always being available, I would instead check for the existance of the process ID by checking if the directory /proc/$PID existed, but not everyone uses proc anymore. That version is currently the one at http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html but I plan on upgrading to this new version soon.

Remove all mail in Postfix mail queue.

Install pip with Proxy
Installs pip packages defining a proxy

Replace spaces in a filename with hyphens
As long as you have perl based rename. You can check: =$ rename --help Unknown option: help Usage: rename [-v] [-n] [-f] perlexpr [filenames] That's the good one.


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