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 20:17:44 891
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Copy from host 1 to host 2 through your host

defragment files
Thanks to flatcap for optimizing this command. This command takes advantage of the ext4 filesystem's resistance to fragmentation. By using this command, files that were previously fragmented will be copied / deleted / pasted essentially giving the filesystem another chance at saving the file contiguously. ( unlike FAT / NTFS, the *nix filesystem always try to save a file without fragmenting it ) My command only effects the home directory and only those files with your R/W (read / write ) permissions. There are two issues with this command: 1. it really won't help, it works, but linux doesn't suffer much (if any ) fragmentation and even fragmented files have fast I/O 2. it doesn't discriminate between fragmented and non-fragmented files, so a large ~/ directory with no fragments will take almost as long as an equally sized fragmented ~/ directory The benefits i managed to work into the command: 1. it only defragments files under 16mb, because a large file with fragments isn't as noticeable as a small file that's fragmented, and copy/ delete/ paste of large files would take too long 2. it gives a nice countdown in the terminal so you know how far how much progress is being made and just like other defragmenters you can stop at any time ( use ctrl+c ) 3. fast! i can defrag my ~/ directory in 11 seconds thanks to the ramdrive powering the command's temporary storage bottom line: 1. its only an experiment, safe ( i've used it several times for testing ), but probably not very effective ( unless you somehow have a fragmentation problem on linux ). might be a placebo for recent windows converts looking for a defrag utility on linux and won't accept no for an answer 2. it's my first commandlinefu command

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

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"

exec chmod to subfiles
Using `-exec cmd {} +` causes find to build the command using all matching filenames before execution, rather than once per file.

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

lotto generator

Search files with js declarations inside
Useful to crawl where the javascript is declared, and extract it a common file. You can redirect it to a file to review item by item.

Reducing image size
Adding the exclamation mark to the image geometry ignores the original aspect ratio. More info about image geometry: http://www.imagemagick.org/script/command-line-processing.php#geometry

To find which host made maximum number of specific tcp connections
This command is primarily going to work on linux boxes. and needs to be changed, for example IP=10\.194\.194\.2 PORT=389


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