All commands (14,187)

  • will show: installed linux headers, image, or modules: /^ii/!d avoiding current kernel: /'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d only application names: s/^[^ ]* [^ ]* \([^ ]*\).*/\1/ avoiding stuff without a version number: /[0-9]/!d Show Sample Output


    4
    dpkg -l 'linux-*' | sed '/^ii/!d;/'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d;s/^[^ ]* [^ ]* \([^ ]*\).*/\1/;/[0-9]/!d'
    plasticdoc · 2009-06-19 10:23:38 8
  • will purge: only installed apps: /^ii/!d avoiding current kernel stuff: /'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d using app names: s/^[^ ]* [^ ]* \([^ ]*\).*/\1/ avoiding stuff without a version number: /[0-9]/!d


    7
    dpkg -l 'linux-*' | sed '/^ii/!d;/'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d;s/^[^ ]* [^ ]* \([^ ]*\).*/\1/;/[0-9]/!d' | xargs sudo apt-get -y purge
    plasticdoc · 2009-06-19 10:11:00 9
  • This commands will make it easier to select only common items between two files being compared. If your lines start with things other than lowercase a-z, adjust this Regex appropriately. Number of lines in the output has been set to no more than 10000, and should be adjusted as needed.


    -1
    gdiff --unified=10000 input.file1 inpute.file2 | egrep -v "(^\+[a-z]|^\-[a-z])"| sort > outputfile.sorted
    slashdot · 2009-06-18 20:35:00 8
  • Stuck behind a restrictive firewall at work, but really jonesing to putty home to your linux box for some colossal cave? Goodness knows I was...but the firewall at work blocked all outbound connections except for ports 80 and 443. (Those were wide open for outbound connections.) So now I putty over port 443 and have my linux box redirect it to port 22 (the SSH port) before it routes it internally. So, my specific command would be: iptables -t nat -A PREROUTING -p tcp --dport 443 -j REDIRECT --to-ports 22 Note that I use -A to append this command to the end of the chain. You could replace that with -I to insert it at the beginning (or at a specific rulenum). My linux box is running slackware, with a kernel from circa 2001. Hopefully the mechanics of iptables haven't changed since then. The command is untested under any other distros or less outdated kernels. Of course, the command should be easy enough to adapt to whatever service on your linux box you're trying to reach by changing the numbers (and possibly changing tcp to udp, or whatever). Between putty and psftp, however, I'm good to go for hours of time-killing.


    10
    iptables -t nat -A PREROUTING -p tcp --dport [port of your choosing] -j REDIRECT --to-ports 22
    brizznown · 2009-06-18 17:38:59 11
  • additionally use "find /etc/cron*" for cronscripts Show Sample Output


    1
    cut -d: -f1 /etc/passwd | grep -vE "#" | xargs -i{} crontab -u {} -l
    hoberion · 2009-06-18 16:49:52 9
  • Sometimes you're trying to read through an xml file to determine whats wrong with it and a tool had removed all the linebreaks. xmllint will go ahead and make it pretty for you.


    4
    xmllint --format <filename> > <output file>
    topperge · 2009-06-18 15:00:30 6

  • 0
    shred -vzu /tmp/junk-file-to-be-shredded
    mpb · 2009-06-18 12:00:19 11
  • imports a public key from the web. I know this by head.. but useful nevertheless Show Sample Output


    2
    curl -s http://defekt.nl/~jelle/pubkey.asc | gpg --import
    wires · 2009-06-18 11:26:03 9
  • Appended to grub boot parameters ... gives shell ... password recovery


    2
    init=/bin/bash; mount -o remount,rw /
    m03hr3 · 2009-06-18 08:51:24 6
  • I had some trouble removing empty lines from a file (perhaps due to utf-8, as it's the source of all evil), \W did the trick eventually.


    0
    grep -v "^\W$" <filename>
    nikc · 2009-06-18 08:17:22 17

  • 2
    find directory -size +nnn
    miccaman · 2009-06-18 06:55:00 6

  • 1
    ls -s | sort -nr | more
    miccaman · 2009-06-18 06:44:01 29
  • Starts midnightcommander and allows you to detach the console; use ctrl-\ to detach Then at a later time you can reconnect using dtach -a /tmp/wires-mc In my experience dtach works much better for programs like irssi, mutt, mc, aptitude than screen does.


    5
    dtach -c /tmp/wires-mc mc
    wires · 2009-06-17 22:18:25 12
  • search the newest *.jpg in the directory an make a copy to newest.jpg. Just change the extension to search other files. This is usefull eg. if your webcam saves all pictures in a folder and you like the put the last one on your homepage. This works even in a directory with 10000 pictures.


    1
    cp `ls -x1tr *.jpg | tail -n 1` newest.jpg
    Psychodad · 2009-06-17 20:32:04 9
  • Using the grep command, retrieve all lines from any log files in /var/log/ that have one of the problem states


    6
    grep -2 -iIr "err\|warn\|fail\|crit" /var/log/*
    miketheman · 2009-06-17 19:41:04 10
  • This will create a 10 MB file named testfile.txt. Change the count parameter to change the size of the file. As one commenter pointed out, yes /dev/random can be used, but the content doesn't matter if you just need a file of a specific size for testing purposes, which is why I used /dev/zero. The file size is what matters, not the content. It's 10 MB either way. "Random" just referred to "any file - content not specific" Show Sample Output


    1
    dd if=/dev/zero of=testfile.txt bs=1M count=10
    mstoecker · 2009-06-17 17:06:16 14

  • 2
    qlook() { qlmanage -p "$@" >& /dev/null & }
    mikedamage · 2009-06-17 16:02:34 5

  • 7
    pbpaste > newfile.txt
    mikedamage · 2009-06-17 15:14:22 8
  • Makes any files in the current directory (and any sub-directories) group-readable. Using the "! -perm /g=r" limits the number of files to only those that do not already have this property Using "+" on the end of the -exec body tells find to build the entire command by appending all matching files before execution, so invokes chmod once only, not once per file.


    3
    find . -type f ! -perm /g=r -exec chmod g+r {} +
    sanmiguel · 2009-06-17 13:39:59 5
  • Makes it easy to add keys to new ppa sources entries in apt sources.list Now to add the key for the chromium-daily ppa: launchpadkey 4E5E17B5 Show Sample Output


    9
    alias launchpadkey="sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys"
    azeey · 2009-06-17 12:02:27 10
  • Useful if you have to put together multiple files into one and they are scattered across subdirectories. For example: You need to combine all .sql files into one .sql file that would be sent to DBAs as a batch script. You do get a warning if you create a file by the same extension as the ones your searching for. find . -type f -name *.sql -exec cat {} > BatchFile.txt \;


    4
    find . -type f -name *.ext -exec cat {} > file.txt \;
    realgt · 2009-06-17 11:33:14 15
  • There are two ways to use "here documents" with bash to fill stdin: The following example shows use with the "bc" command. a) Using a delimiter at the end of data: less-than less-than eeooff bc > k=1024 > m=k*k > g=k*m > g > eeooff 1073741824 b) using the "inline" verion with three less-than symbols: less-than less-than less-than "k=1024; m=k*k; g=k*m; g" bc 1073741824 One nice advantage of using the triple less-than version is that the command can easily be recalled from command line history and re-executed. PS: in this "description", I had to use the name "less-than" to represent the less-than symbol because the commandlinefu input text box seems to eat up the real less-than symbols. Odd. Show Sample Output


    9
    <<<"k=1024; m=k*k; g=k*m; g" bc
    mpb · 2009-06-17 10:35:10 12
  • You need sysstat and gawk for this to work. Show Sample Output


    0
    for x in `seq -w 1 30`; do sar -b -f /var/log/sa/sa$x | gawk '/Average/ {print $2}'; done
    unixmonkey4319 · 2009-06-17 02:46:52 4
  • This set of commands was very convenient for me when I was preparing some xml files for typesetting a book. I wanted to check what styles I had to prepare but coudn't remember all tags that I used. This one saved me from error-prone browsing of all my files. It should be also useful if one tries to process xml files with xsl, when using own xml application.


    2
    grep -h -o '<[^/!?][^ >]*' * | sort -u | cut -c2-
    thebodzio · 2009-06-17 00:22:18 10
  • In the above example all files have 4 lines. In "file1" consecutive lines are: "num, 1, 2, 3", in "file2": "name, Jack, Jim, Frank" and in "file3": "scores, 1300, 1100, 980". This one liner can save considerate ammount of time when you're trying to process serious portions of data. "-d" option allows one to set series of characters to be used as separators between data originating from given files. Show Sample Output


    8
    paste -d ',:' file1 file2 file3
    thebodzio · 2009-06-17 00:11:04 12
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Check wireless link quality with dialog box
The variable WIRELESSINTERFACE indicates your wireless interface

Quick screenshot
Requires ImageMagick. Takes a screenshot 5 seconds after it's run and saves it as desktop_screenshot.jpg Particularly handy when made into a menu option or button.

Find usb device
I often use it to find recently added ou removed device, or using find in /dev, or anything similar. Just run the command, plug the device, and wait to see him and only him

vim multiple files at one time, split vertically.

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Convert all WMF images to SVG recursively ignoring file extension case
This assumes you have the package installed necessary for converting WMF files. On my Ubuntu box, this is libwmf-bin. I used this command, as libwmf is not on my wife's iMac, so I archived the directories containing the WMF files from OS X, ran them on my Ubuntu box, archived the resulting SVGs, and sent them back to her. Quick, simple and to the point. Searches directories recursively looking for extensions ignoring case. This is much more readable and clean than -exec for find. The while loop also gives further flexibility on complex logic. Also, although there is 'wmf2svg --auto', it expects lowercase extensions, and not uppercase. Because I want to ignore case, I need to use the -o option instead. Works in ZSH and BASH. Haven't tested in other shells.

Replace all in last command

Find the package that installed a command

GREP a PDF file.
PDF files are simultaneously wonderful and heinous. They are wonderful in being ubiquitous and mostly being cross platform. They are heinous in being very difficult to work with from the command line, search, grep, use only the text inside the PDF, or use outside of proprietary products. xpdf is a wonderful set of PDF tools. It is on many linux distros and can be installed on OS X. While primarily an open PDF viewer for X, xpdf has the tool "pdftotext" that can extract formated or unformatted text from inside a PDF that has text. This text stream can then be further processed by grep or other tool. The '-' after the file name directs output to stdout rather than to a text file the same name as the PDF. Make sure you use version 3.02 of pdftotext or later; earlier versions clipped lines. The lines extracted from a PDF without the "-layout" option are very long. More paragraphs. Use just to test that a pattern exists in the file. With "-layout" the output resembles the lines, but it is not perfect. xpdf is available open source at http://www.foolabs.com/xpdf/

Determine whether a CPU has 64 bit capability or not


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