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 The command is untested under any other distros or less outdated kernels.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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Replicate a directory structure dropping the files

find out how many days since given date
You can also do this for seconds, minutes, hours, etc... Can't use dates before the epoch, though.

Count number of files in subdirectories
For each directory from the current one, list the counts of files in each of these directories. Change the -maxdepth to drill down further through directories.

Adequately order the page numbers to print a booklet
Useful if you don't have at hand the ability to automatically create a booklet, but still want to. F is the number of pages to print. It *must* be a multiple of 4; append extra blank pages if needed. In evince, these are the steps to print it, adapted from https://help.gnome.org/users/evince/stable/duplex-npage.html.en : 1) Click File ▸ Print. 2) Choose the General tab. Under Range, choose Pages. Type the numbers of the pages in this order (this is what this one-liner does for you): n, 1, 2, n-1, n-2, 3, 4, n-3, n-4, 5, 6, n-5, n-6, 7, 8, n-7, n-8, 9, 10, n-9, n-10, 11, 12, n-11... ...until you have typed n-number of pages. 3) Choose the Page Setup tab. - Assuming a duplex printer: Under Layout, in the Two-side menu, select Short Edge (Flip). - If you can only print on one side, you have to print twice, one for the odd pages and one for the even pages. In the Pages per side option, select 2. In the Page ordering menu, select Left to right. 4) Click Print.

Sort files by date
Show you the list of files of current directory sorted by date youngest to oldest, remove the 'r' if you want it in the otherway.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

reverse-i-search: Search through your command line history
"What it actually shows is going to be dependent on the commands you've previously entered. When you do this, bash looks for the last command that you entered that contains the substring "ls", in my case that was "lsof ...". If the command that bash finds is what you're looking for, just hit Enter to execute it. You can also edit the command to suit your current needs before executing it (use the left and right arrow keys to move through it). If you're looking for a different command, hit Ctrl+R again to find a matching command further back in the command history. You can also continue to type a longer substring to refine the search, since searching is incremental. Note that the substring you enter is searched for throughout the command, not just at the beginning of the command." - http://www.linuxjournal.com/content/using-bash-history-more-efficiently

Get the list of local files that changed since their last upload in an S3 bucket
Can be useful to granulary flush files in a CDN after they've been changed in the S3 bucket.

print DateTimeOriginal from EXIF data for all files in folder
see output from `identify -verbose` for other keywords to filter for (e.g. date:create, exif:DateTime, EXIF:ExifOffset).

Change every instance of OLD to NEW in file FILE
Very quick way to change a word in a file. I use it all the time to change variable names in my PHP scripts (sed -i 's/$oldvar/$newvar/g' index.php)


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