Commands tagged kernel (37)

  • Install 4 new package files

    after kernel build with make deb-pkg, I like to install the 4 newest packages that exist in the directory. Beware: might be fewer for you....


    0
    sudo dpkg -i `ls -tr *.deb | tail -n4`
    _john · 2011-10-09 14:20:11 3
  • Output the latest linux kernel versions from kernel.org

    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 4
  • Force a kernel panic

    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 6
  • Turn on NFS Debugging

    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 9
  • Compute newest kernel version from Makefile on Torvalds' git repository

    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 17:12:05 336
  • Compute newest kernel version from Makefile on Torvalds' git repository

    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


    0
    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 22:25:55 136
  • [Gentoo] Input modules, commented, in your module.autoload file

    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 4
  • Disable ASLR

    Disable randomisation address Show Sample Output


    -1
    echo 0 > /proc/sys/kernel/randomize_va_space
    gunslinger_ · 2010-07-11 16:42:42 3
  • Remove all unused kernels with apt-get

    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 3
  • Get current stable kernel version string from kernel.org

    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 7
  • Remove all unused kernels with apt-get


    -4
    aptitude purge linux-image | grep ^i | grep -v $(uname -r)
    lgallardo · 2010-06-11 22:20:42 5
  • Check if system is 32bit or 64bit

    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 15
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Generate QR code for a WiFi hotspot
Prompts for network name (SSID) and password, and generates (as qr-wifi.png) a WiFi QR code (e.g. "WIFI:S:mynet;T:WPA;P:mypass;;" for mynet/mypass). Dependencies [sudo apt-get install]: qrencode zenity

grep across a git repo and open matching files in gedit

Block all FaceBook traffic

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.

Performance tip: compress /usr/
Periodically run the one-liner above if/when there are significant changes to the files in /usr/ = Before rebooting, add following to /etc/fstab : = $ /squashed/usr/usr.sfs /squashed/usr/ro squashfs loop,ro 0 0 $ usr /usr aufs udba=reval,br:/squashed/usr/rw:/squashed/usr/ro 0 0 No need to delete original /usr/ ! (unless you don't care about recovery). Also AuFS does not work with XFS

Delete all files in a folder that don't match a certain file extension
Deletes all files in a folder that are NOT *.foo, *.bar or *.baz files. Edit the pattern inside the brackets as you like.

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Push your present working directory to a stack that you can pop later
If are a Bash user and you are in a directory and need to go else where for a while but don't want to lose where you were, use pushd instead of cd. cd /home/complicated/path/.I/dont/want/to/forget pushd /tmp cd thing/in/tmp popd (returns you to /home/complicated/path/.I/dont/want/to/forget)

Create a backup of file being edited while using vi
At the start of a vi session and *before* saving any changes use ":!cp % %-" to make a backup of the current file being edited. example: vi /data/some/long/path/file :!cp% %- creates /data/some/long/path/file-

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