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 20:17:44 884
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Watch YouTube and other Flash videos via mplayer (or whatever)
Many sites with Flash video players will download video files to /tmp on Linux, with temporary filenames like "FlashbGTHm4". These will often play in mplayer, totem, or other movie playing software. You must first navigate to a video page, let it start loading, and then pause playback.

nmap fast scan all ports target

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Complex string encoding with sed
Pipe | avoid escaping occurences problems in using sed and make it easier to use

validate json
I have this saved as jsonlint chmodded +x and file.js is instead $1, but YMMV

Google Spell Checker
I took matthewbauer's cool one-liner and rewrote it as a shell function that returns all the suggestions or outputs "OK" if it doesn't find anything wrong. It should work on ksh, zsh, and bash. Users that don't have tee can leave that part off like this: $spellcheck(){ typeset y=$@;curl -sd "$y" https://google.com/tbproxy/spell|sed -n '/s="[1-9]"/{s/]*>/ /g;s/\t/ /g;s/ *\(.*\)/Suggestions: \1\n/g;p}';}

Find the ratio between ram usage and swap usage.
it provides the ratio used for the RAM and The SWAP under Linux. When swappiness is high, Swap usage is high. When swappiness is low, Ram usage is high.

Runs a command without hangups.
The improvement is that you can re-attach to the screen at a later point.

Change Title of Terminal Window to Verbose Info useful at Login
I usually have 5 or more ssh connections to various servers, and putting this command in my .bash_profile file makes my putty window or x terminal window title change to this easily recognizable and descriptive text. Includes the username, group, server hostname, where I am connecting from (for SSH tunneling), which device pts, current server load, and how many processes are running. You can also use this for your PROMPT_COMMAND variable, which updates the window title to the current values each time you exec a command. I prefix running this in my .bash_profile with $ [[ ! -z "$SSH_TTY" ]] && which makes sure it only does this when connecting via SSH with a TTY. Here's some rougher examples from http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html $ # If set, the value is executed as a command prior to issuing each primary prompt. $ #H=$((hostname || uname -n) 2>/dev/null | sed 1q);W=$(whoami) $ #export PROMPT_COMMAND='echo -ne "\033]0;${W}@${H}:${PWD/#$HOME/~} ${SSH_TTY/\/dev\//} [`uptime|sed -e "s/.*: \([^,]*\).*/\1/" -e "s/ //g"`]\007"' $ #PROMPT_COMMAND='echo -ne "\033]0;`id -un`:`id -gn`@`hostname||uname -n 2>/dev/null|sed 1q` `command who -m|sed -e "s%^.* \(pts/[0-9]*\).*(\(.*\))%[\1] (\2)%g"` [`uptime|sed -e "s/.*: \([^,]*\).*/\1/" -e "s/ //g"` / `command ps aux|wc -l`]\007"' $ #[[ -z "$SSH_TTY" ]] || export PROMPT_COMMAND $ #[[ -z "$SSH_TTY" ]] && [[ -f /dev/stdout ]] && SSH_TTY=/dev/stdout And here's a simple function example for setting the title: $ function set_window_title(){ echo -e "\033]0; ${1:-$USER@$HOST - $SHLVL} \007"; }

Get info about a GitHub project
In this example we search for 'vim' but vim doesn't have a project on github right now. That's ok, this command still searches for every project that has 'vim' in their description (forks, plugins, etc). To get XML or JSON output just replace 'yaml' in the url with 'xml' or 'json'.


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