All commands (14,187)

  • This is a handy way to circumvent the "Maximum line length of 2048 exceeded" grep error. Once you have run the above command (or put it in your .bashrc), files can be searched using: lgrep search-string /file/to/search


    1
    lgrep() { string=$1; file=$2; awk -v String=${string} '$0 ~ String' ${file}; }
    dopeman · 2010-01-19 09:42:19 3
  • To also move the db backup to another location you could pass the output to the dd command instead of a file mysqldump -u user -h host -ppwd -B dbname | bzip2 -zc9 | dd ssh usr@server "dd of=db_dump"


    1
    mysqldump -u user -h host -ppwd -B dbname | bzip2 -zc9 > dbname.sql.bz2
    olaseni · 2010-01-19 07:34:21 3

  • 1
    perl -i~ -0777pe's/^/\!\#\/usr\/bin\/ksh\n/' testing
    azil · 2010-01-19 06:49:10 4
  • This command defragment the SQLite databases found in the home folder of the current Windows user. This is usefull to speed up Firefox startup. The executable sqlite3.exe must be located in PATH or in the current folder. In a script use: for /f "delims==" %%a in (' dir "%USERPROFILE%\*.sqlite" /s/b ') do echo vacuum;|"sqlite3.exe" "%%a" Show Sample Output


    -3
    for /f "delims==" %a in (' dir "%USERPROFILE%\*.sqlite" /s/b ') do echo vacuum;|"sqlite3.exe" "%a"
    vutcovici · 2010-01-18 20:56:00 6
  • It's very common to have cron jobs that send emails as their output, but the From: address is whatever account the cron job is running under, which is often not the address you want replies to go to. Here's a way to change the From: address right on the command line. What's happening here is that the "--" separates the options to the mail client from options for the sendmail backend. So the -f and -F get passed through to sendmail and interpreted there. This works on even on a system where postfix is the active mailer - looks like postfix supports the same options. I think it's possible to customize the From: address using mutt as a command line mailer also, but most servers don't have mutt preinstalled.


    10
    mail -s "subject" user@todomain.com <emailbody.txt -- -f customfrom@fromdomain.com -F 'From Display Name'
    dmmst19 · 2010-01-18 19:55:27 30
  • if firefox is running the database is locked, so you need to copy the places.sqlite file temporarily somewhere to be able to query it...


    2
    sqlite3 -list /home/$USER/.mozilla/firefox/*.default/places.sqlite 'select url from moz_places ;' | grep http
    bubo · 2010-01-18 15:25:00 3
  • http://www.mplayerhq.hu/DOCS/HTML/en/menc-feat-mpeg.html MEncoder can create MPEG (MPEG-PS) format output files. Usually, when you are using MPEG-1 or MPEG-2 video, it is because you are encoding for a constrained format such as SVCD, VCD, or DVD. To change MEncoder's output file format, use the -of mpeg option. Creating an MPEG-1 file suitable to be played on systems with minimal multimedia support, such as default Windows installs: mencoder input.avi -of mpeg -mpegopts format=mpeg1:tsaf:muxrate=2000 \ -o output.mpg -oac lavc -lavcopts acodec=mp2:abitrate=224 -ovc lavc \ -lavcopts vcodec=mpeg1video:vbitrate=1152:keyint=15:mbd=2:aspect=4/3


    1
    mencoder input.avi -of mpeg -ovc lavc -lavcopts vcodec=mpeg1video \ -oac copy other_options -o output.mpg
    slishan · 2010-01-18 13:12:03 3
  • Also look at xload


    1
    tload -s 10
    chinmaya · 2010-01-18 08:14:06 3

  • 0
    purple-remote "setstatus?status=Available&message=Checking libpurple"
    spsneo · 2010-01-17 23:48:17 4
  • Note: you'll want to set up pub-key ssh auth. Gives you a quick means of changing volume/tracks/etc for rhythmbox on a remote machine. E.g.: rc --next # Play next track rc --print-playing # Grab the name rc --volume-down rc --help


    9
    alias rc='ssh ${MEDIAPCHOSTNAME} env DISPLAY=:0.0 rhythmbox-client --no-start'
    rhythmx · 2010-01-17 19:43:43 6

  • -1
    watch -n 7 -d 'uptime | sed s/.*users?, //'
    matthewbauer · 2010-01-17 18:45:52 3
  • cat - concatenate MP3 files and save it... Show Sample Output


    -4
    # cat file1.mp3 file2.mp3 > file3.mp3
    svnlabs · 2010-01-17 13:18:34 5
  • CHANGELOG Version 1.1 removedir () { echo "You are about to delete the current directory $PWD Are you sure?"; read human; if [[ "$human" = "yes" ]]; then blah=$(echo "$PWD" | sed 's/ /\\ /g'); foo=$(basename "$blah"); rm -Rf ../$foo/ && cd ..; else echo "I'm watching you" | pv -qL 10; fi; } BUG FIX: Folders with spaces Version 1.0 removedir () { echo "You are about to delete the current directory $PWD Are you sure?"; read human; if [[ "$human" = "yes" ]]; then blah=`basename $PWD`; rm -Rf ../$blah/ && cd ..; else echo "I'm watching you" | pv -qL 10; fi; } BUG FIX: Hidden directories (.dotdirectory) Version 0.9 rmdir () { echo "You are about to delete the current directory $PWD. Are you sure?"; read human; if [[ "$human" = "yes" ]]; then blah=`basename $PWD`; rm -Rf ../$blah/ && cd ..; else echo "I'm watching you" | pv -qL 10; fi; } Removes current directory with recursive and force flags plus basic human check. When prompted type yes 1. [user@host ~]$ ls foo bar 2. [user@host ~]$ cd foo 3. [user@host foo]$ removedir 4. yes 5. rm -Rf foo/ 6. [user@host ~]$ 7. [user@host ~]$ ls bar Show Sample Output


    -2
    removedir () { echo "Deleting the current directory $PWD Are you sure?"; read human; if [[ "$human" = "yes" ]]; then blah=$(echo "$PWD" | sed 's/ /\\ /g'); foo=$(basename "$blah"); rm -Rf ../$foo/ && cd ..; else echo "I'm watching you" | pv -qL 10; fi; }
    oshazard · 2010-01-17 11:34:38 31
  • Combines a few repetitive tasks when compiling source code. Especially useful when a hypen in a file-name breaks tab completion. 1.) wget source.tar.gz 2.) tar xzvf source.tar.gz 3.) cd source 4.) ls From there you can run ./configure, make and etc. Show Sample Output


    -1
    wtzc () { wget "$@"; foo=`echo "$@" | sed 's:.*/::'`; tar xzvf $foo; blah=`echo $foo | sed 's:,*/::'`; bar=`echo $blah | sed -e 's/\(.*\)\..*/\1/' -e 's/\(.*\)\..*/\1/'`; cd $bar; ls; }
    oshazard · 2010-01-17 11:25:47 3

  • 2
    echo -e "swap=me\n1=2"|sed 's/\(.*\)=\(.*\)/\2=\1/g'
    axelabs · 2010-01-16 22:01:37 3
  • Will find all files containing "sample" in the current directory and in the directories below.


    -9
    find . -exec grep -l "sample" {} \;
    whoami · 2010-01-16 13:12:52 4

  • 6
    mwiki () { blah=`echo $@ | sed -e 's/ /_/g'`; dig +short txt $blah.wp.dg.cx; }
    oshazard · 2010-01-16 07:13:43 3
  • This is very similar to the first example except that it employs the 'exec' argument of the find command rather than piping the result to xargs. The second example is nice and tidy but different *NIXs may not have as capable a grep command.


    -1
    find . -name "*.php" -exec grep -il searchphrase {} \;
    unixmonkey7797 · 2010-01-16 05:09:30 4
  • I use this command (PS1) to show a list bash prompt's special characters. I tested it against A flavor of Red Hat Linux and Mac OS X Show Sample Output


    3
    alias PS1="man bash | sed -n '/ASCII bell/,/end a sequence/p'"
    haivu · 2010-01-15 23:39:28 3

  • -2
    hdid somefile.dmg
    rnoyfb · 2010-01-15 12:00:48 5
  • If you really _must_ use a loop, this is better than parsing the output of 'ps': PID=$! ;while kill -0 $PID &>/dev/null; do sleep 1; done kill -0 $PID returns 0 if the process still exists; otherwise 1


    0
    wait
    bhepple · 2010-01-15 04:03:11 5

  • -4
    dd if=/dev/zero of=/tmp/bigfile bs=1024k count=100
    wincus · 2010-01-15 00:44:44 4
  • shorter :p Show Sample Output


    2
    grep -rHi searchphrase *.php
    psybermonkey · 2010-01-15 00:23:25 5
  • This command will find all files recursively containing the phrase entered, represented here by "searchphrase". This particular command searches in all php files, but you could change that to just be html files or just log files etc. Show Sample Output


    2
    find . -name "*.php" | xargs grep -il searchphrase
    refrax · 2010-01-14 22:42:36 5
  • This will output the characters at 10 per second.


    124
    echo "You can simulate on-screen typing just like in the movies" | pv -qL 10
    dennisw · 2010-01-14 20:17:44 876
  • ‹ First  < 408 409 410 411 412 >  Last ›

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands


Check These Out

nohup that doesn't generate nohup.out
I'm sure this can be piped into another way. Please share!

Crash bash, in case you ever want to for whatever reason
This is a very hackish way to do it that I'm mainly just posting for fun, and I guess technically can more accurately be said to result in undefined behavior. What the command does is tell the shell to treat libpng like it's a shell plugin (which it's most certainly not) and attempt to install a "png_create_read" command from the library. It looks for the struct with the information about the command; since it's always the command name followed by "_struct", it'll look for a symbol called "png_create_read_struct". And it finds it, since this is the name of one of libpng's functions. But bash has no way to tell it's a function instead of a struct, so it goes ahead and parses the function's code as if it was command metadata. Inevitably, bash will attempt to dereference an invalid pointer or whatever, resulting in a segfault.

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

find text in a file
this will find text in the directory you specify and give you line where it appears.

Automator Bash script to create Clean zips in MacOS Finder without __MACOSX metadata
Finder compresses to ZIP but always includes extraneous metadata files (__MACOSX and .DS_Store) files and folders that may confuse other programs. One alternative is creating them and then editing the ZIP. This can work standalone or in an automator script accepting multiple selections (files or folders) and creating one zip per argument/selected file without that metada.

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

list block devices
Shows all block devices in a tree with descruptions of what they are.

create an screenshot, upload it to your server via scp and then open that screenshot in firefox
I often need to send screenshots to other people to explain settings and whatever. So I created this oneline which I use to create the screenshot with imagemagik, upload it via scp to my server and then the command opens an firefox tab with the screenshot. The screenshot can be a region or a window. You just have to replace the parts beginning with YOUR.

Daemonize nc - Transmit a file like a http server
Allow to launch nc like a daemon, in background until you still stop it. You can stop it with kill %1 (jobs method) or kill PID. The -k option can force nc to listen another connection, but if you use redirection, it will work only one time. The loop's inside doesn't do anything, but we can imagine to send a message to screen when a connection is established

Advanced python tracing
Trace python statement execution and syscalls invoked during that simultaneously


Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for: