Commands tagged Ubuntu (92)


  • 3
    dpkg -l
    linuxrawkstar · 2011-10-17 16:26:29 3

  • 3
    dpkg -l linux-* | awk '/^ii/{ print $2}' | grep -v -e `uname -r | cut -f1,2 -d"-"` | grep -e [0-9] | xargs sudo apt-get -y purge
    yusufk · 2014-01-29 10:42:40 5
  • Compares two versions with dpkg. It is not always obvious what version dpkg/apt will consider to be more recent. Operators include the following : * These treat an empty version as earlier than any version: lt le eq ne ge gt. * These treat an empty version as later than any version: lt-nl le-nl ge-nl gt-nl. * These are provided only for compatibility with control file syntax: < > >. This command doesn't output anything. It only returns with status 0 or 1, hence the echo "y" || echo "n" to get an output. Show Sample Output


    2
    dpkg --compare-versions 1.0-2ubuntu5 lt 1.1-1~raphink3 && echo y || echo n
    raphink · 2009-02-28 18:01:59 5
  • Lets you set all the java alternatives at once to a matching version. Also has options for just changing the jre or the plugin.


    2
    update-java-alternatives
    stuart · 2009-08-09 02:43:06 6
  • This command will transcode a MythTV recording. The target device is a Google Nexus One mobile phone. My recordings are from a HDHomerun with Over The Air content. Plays back nicely on the N1.


    2
    ffmpeg -i /var/lib/mythtv/pretty/Chuck20100208800PMChuckVersustheMask.mpg -s 800x480 -vcodec mpeg4 -acodec libfaac -ac 2 -ar 16000 -r 13 -ab 32000 -aspect 16:9 Chuck20100208800PMChuckVersustheMask.mp4
    PLA · 2010-02-12 12:11:02 7
  • if you haven't already done so, install lame and flac: sudo apt-get install lame flac Show Sample Output


    2
    flac -cd input.flac |lame -h - output.mp3
    nickleus · 2010-03-05 23:54:21 4
  • Change the APP variable's value to whatever you want to install. Depending on how fast your machine is, you'll want to adjust the value 50 to something else. You might also want to play a different game than Gnometris - just make sure it's a GUI game.


    2
    APP=wine; if [ $(sudo apt-get --print-uris -y install $APP | sed -ne 's/^After this operation, \([0-9]\{1,\}\).*MB.*/\1/p') -gt 50 ]; then gnometris 2>/dev/null & sudo apt-get install $APP; else sudo apt-get install $APP; fi
    rkulla · 2010-04-18 19:32:26 39
  • As of 10.04 LTS, you need to use this command-line to reports bugs to the launchpad.net tracking system (you need a launchpad acct for this to work). This command is preferred over using the website because it collects/sends info about your system to help developers. ubuntu-bug is a symlink to apport-bug which sees if KDE/Gnome is running and calls apport-gtk/apport-kde dialogs, otherwise apport-cli, so you can fill out a bug report. First run 'ubuntu-bug' without args to see a list of known symptoms. If there's no matching symptom, or you know which package is to blame, then run 'ubuntu-bug <package>'. If the process is still running, use 'ubuntu-bug <PID>'


    2
    ubuntu-bug
    rkulla · 2010-05-02 20:24:32 3
  • i have a large video file, 500+ MB, so i cant upload it to flickr, so to reduce the size i split it into 2 files. the command shows the splitting for the first file, from 0-4 minutes. ss is start time and t is duration (how long you want the output file to be). credit goes to philc: http://ubuntuforums.org/showthread.php?t=480343 NOTE: when i made the second half of the video, i got a *lot* of lines like this: frame= 0 fps= 0 q=0.0 size= 0kB time=10000000000.00 bitrate= 0.0kbit just be patient, it is working =) Show Sample Output


    2
    ffmpeg -i 100_0029.MOV -ss 00:00:00 -t 00:04:00 100_0029_1.MOV
    nickleus · 2010-08-08 23:43:28 3
  • this will open a new tab in firefox for every line in a file the sleep is removable but i found that if you have a large list of urls 50+, and no sleep, it will try to open all the urls at once and this will cause them all to load a lot slower, also depending on the ram of your system sleep gives you a chance to close the tabs before they overload your ram, removing & >2/dev/null will yield unpredictable results.


    2
    for line in `cat $file`; do firefox -new-tab "$line" & 2>/dev/null; sleep 1; done
    hamsolo474 · 2011-11-12 13:47:24 3
  • This script will run each time you boot up.The script must be in /etc/init.d directory.


    2
    sudo update-rc.d <scriptname> defaults
    Dhinesh · 2011-11-19 08:55:38 6
  • This handles when you have a single call or channel. Other commands will strip out the result if there is a single channel or call active because the output changes the noun to be singular instead of plural. Show Sample Output


    2
    watch "asterisk -vvvvvrx 'core show channels' | egrep \"(call|channel)\""
    rowshi · 2012-08-29 13:40:45 5
  • Requires: curl xsel access to the internet(http://transfer.sh) This is an alias utilizing the transfer.sh service to make sharing files easier from the command line. I have modified the alias provided by transfer.sh to use xsel to copy the resulting URL to the clipboard. The full modified alias is as follows since commandlinefu only allows 255 characters: transfer() { if [ $# -eq 0 ]; then echo "No arguments specified. Usage:\necho transfer /tmp/test.md\ncat /tmp/test.md | transfer test.md"; return 1; fi if tty -s; then basefile=$(basename "$1" | sed -e 's/[^a-zA-Z0-9._-]/-/g'); curl --progress-bar --upload-file "$1" "https://transfer.sh/$basefile" |xsel --clipboard; else curl --progress-bar --upload-file "-" "https://transfer.sh/$1" |xsel --clipboard ; fi; xsel --clipboard; } Show Sample Output


    2
    transfer() { basefile=$(basename "$1" | sed -e 's/[^a-zA-Z0-9._-]/-/g');curl --progress-bar --upload-file "$1" "https://transfer.sh/$basefile"|xsel --clipboard;xsel --clipboard ; }
    leftyfb · 2016-03-20 19:38:48 12
  • I put this command on my ~/.bashrc in order to learn something new about installed packages on my Debian/Ubuntu system each time I open a new terminal Show Sample Output


    2
    dpkg-query --status $(dpkg --get-selections | awk '{print NR,$1}' | grep -oP "^$( echo $[ ( ${RANDOM} % $(dpkg --get-selections| wc -l) + 1 ) ] ) \K.*")
    acavagni · 2019-06-01 13:24:07 45
  • Displays only the VGA adapter/chipset being used for the graphics. In this case, it gave me the "M22" and "Mobility Radeon x300" that I needed to research a graphics issue I was having. Show Sample Output


    1
    lspci |grep VGA
    CafeNinja · 2009-04-28 08:34:42 9
  • Use sed to comment out any up/down bindings in zsh


    1
    sudo sed -iorig '/\(up\|down\)/s/^/#/' /etc/zsh/zshrc
    cbrinker · 2010-02-02 23:17:08 27
  • I had problems in Ubuntu while trying to edit /etc/resolv.conf, even with sudo I couldn't make any change. After a 2 minutes search on google I found this command. Hope someone finds it useful. It works like chmod, with + and - to denote which attributes are being added and which are being removed. See other attributes on man pages or on wikipedia http://en.wikipedia.org/wiki/Chattr


    1
    sudo chattr -i <file that cannot be modified>
    leovailati · 2010-03-25 03:14:34 4
  • Only the number of calls nothing else. Show Sample Output


    1
    /usr/sbin/asterisk -rx 'core show channels' | grep -m1 "call" | cut -d' ' -f1
    stackoverflow128 · 2012-02-01 17:55:17 5
  • The command tasksel allows the choice of packages from the command line to get predefined configurations for specific services (usually this option is offered during installation).


    1
    tasksel list-tasks
    0disse0 · 2012-02-03 16:13:17 5
  • Bash snippet to force GNU/Linux keyboard settings, layout and configuration. Usefull when some GNU/Linux distributions such as *Ubuntu's store only limited configation options due to demonstration purposes on LiveUSB or Live persistent devices. Overcomes the English QWERTY to French AZERTY settings failure. Code bash en ligne de commande pour forcer l'adoption du clavier AZERTY sur les cl? USB bootable en Ubuntu.


    1
    sudo dpkg-reconfigure keyboard-configuration
    arsenerichard · 2012-03-27 21:07:45 47
  • locating packages held back, such as with "aptitude hold "


    1
    aptitude search ~ahold
    pykler · 2012-04-29 15:02:32 4
  • Taken from apticron and modified. Show Sample Output


    1
    apt-get --ignore-hold --allow-unauthenticated -s dist-upgrade | grep ^Inst | cut -d ' ' -f2
    phunehehe · 2013-01-07 11:21:58 4
  • Backs up all databases, excluding test, mysql, performance_schema, information_schema. Requires parallel to work, install parallel on Ubuntu by running: sudo aptitude install parallel


    1
    mysql -e 'show databases' -s --skip-column-names | egrep -v "^(test|mysql|performance_schema|information_schema)$" | parallel --gnu "mysqldump --routines {} > {}_daily.sql"
    intel352 · 2013-07-24 15:37:58 11
  • The other commands were good, but they included packages that were installed and then removed. This command only shows packages that are currently installed, sorts smallest to largest, and formats the sizes to be human readable. Show Sample Output


    1
    dpkg-query --show --showformat='${Package;-50}\t${Installed-Size}\n' `aptitude --display-format '%p' search '?installed!?automatic'` | sort -k 2 -n | grep -v deinstall | awk '{printf "%.3f MB \t %s\n", $2/(1024), $1}'
    EvilDennisR · 2013-07-26 23:18:20 13
  • In this case, linux- is the prefix; simply running apt-cache pkgnames would list every package APT knows about. The default APT config assumes -g, --generate; to use the cache as/is, you could similarly run: apt-cache --no-generate pkgnames [prefix] Adding --all-names, like so: apt-cache --no-generate --all-names pkgnames [prefix] would print all the packages APT knows about, using the cache as/is, including virtual packages and missing dependencies. This command was shamelessly stolen from the apt-cache(8) man-page. Show Sample Output


    1
    apt-cache pkgnames linux-
    benjabean1 · 2014-12-14 06:48:57 8
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File rotation without rename command
Rotates log files with "gz"-extension in a directory for 7 days and enumerates the number in file name. i.e.: logfile.1.gz > logfile.2.gz I needed this line due to the limitations on AIX Unix systems which do not ship with the rename command.

Colorized JSON pretty printing
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Remove a range of lines from a file

Generate Random Passwords
If you want a password length longer than 6, changing the -c6 to read -c8 will give you 8 random characters instead of 6. To end up with a line-feed, use this with echo: # echo `< /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c6` Modern systems need higher strenght, so add some special characters: # < /dev/urandom tr -dc '12345!@#$%qwertQWERTasdfgASDFGzxcvbZXCVB' | head -c8

List all installed PERL modules by CPAN
This command will give you the detailed information about the installed perl modules i.e. installed path, Link type, version, files etc.

open two files on top of each other in vim (one window, two panes)

Find ulimit values of currently running process
When dealing with system resource limits like max number of processes and open files per user, it can be hard to tell exactly what's happening. The /etc/security/limits.conf file defines the ceiling for the values, but not what they currently are, while $ ulimit -a will show you the current values for your shell, and you can set them for new logins in /etc/profile and/or ~/.bashrc with a command like: $ ulimit -S -n 100000 >/dev/null 2>&1 But with the variability in when those files get read (login vs any shell startup, interactive vs non-interactive) it can be difficult to know for sure what values apply to processes that are currently running, like database or app servers. Just find the PID via "ps aux | grep programname", then look at that PID's "limits" file in /proc. Then you'll know for sure what actually applies to that process.

format txt as table

ShellCheck all the bash/sh script under a specific directory excluding version control
This is a commodity one-liner that uses ShellCheck to assure some quality on bash and sh scripts under a specific directory. It ignores the files in .git directory. Just substitute "./.git/*" with "./.svn/*" for older and booring centralized version control. Just substitute ShellCheck with "rm" if your scripts are crap and you want to get rid of them :)

Create higher quality gif from videos
I had to compress it a bit to meet the 255 limit. See sample for full command (274) usage: ffgif foo.ext Supports 3 arguments (optional) ffgif filename seek_time time_duration scale ffgif foo 10 5 320 will seek 10 seconds in, convert for 5 seconds at a 320 scale. Default will convert whole video to gif at 320 scale. Inspiration - http://superuser.com/questions/556029/how-do-i-convert-a-video-to-gif-using-ffmpeg-with-reasonable-quality/556031#556031


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