All commands (14,187)

  • If you should happen to find yourself needing some binary numbers, this is a quickie way of doing it. If you need more digits, just add more "{0..1}" sequences for each digit you need. You can assign them to an array, too, and access them by their decimal equivalent for a quickie binary to decimal conversion (for larger values it's probably better to use another method). Note: this works in bash, ksh and zsh. For zsh, though, you'll need to issue a setopt KSH_ARRAYS to make the array zero-based. binary=({0..1}{0..1}{0..1}{0..1}) echo ${binary[9]} Show Sample Output


    18
    echo {0..1}{0..1}{0..1}{0..1}
    dennisw · 2009-06-23 17:30:20 11
  • order the files by modification (thanks stanishjohnd) time, one file per output line and filter first 10


    7
    ls -1t | head -n10
    wires · 2009-06-23 12:15:12 9
  • ditto can be used to "thinnify" Mach-O Universal binaries to separate unncessary code from your machine. For example, doubleTwist.app shaved off around 10 MB while Google Earth went from 112 MB to 62 MB after extracting only the i386 code from them.


    0
    ditto --arch i386 doubleTwist.app doubleTwist_i386.app
    thebillywayne · 2009-06-22 23:59:14 12
  • Thankfully, the ssh command allows you to specify multiple tunnels through the same server in one command. Remeber if you want a priviliged port on your machine, you must use root or sudo account. Show Sample Output


    9
    ssh -L :: -L :: @
    starchox · 2009-06-22 19:12:48 1652
  • Intended for dynamic ip OpenDNS users, this command will update your OpenDNS network IP. For getting your IP, you can use one of the many one-liners here on commandlinefu. Example: I use this in a script which is run by kppp after it has successfully connected to my ISP: --- #!/bin/bash IP="`curl -s http://checkip.dyndns.org/ | grep -o '[[:digit:].]\+'`" PW="hex-obfuscated-pw-here" if [ "$IP" == "" ] ; then echo 'Not online.' ; exit 1 else wget -q --user=topsecret --password="`echo $PW | xxd -ps -r`" 'https://updates.opendns.com/nic/update?hostname=myhostname&myip='"$IP" -O - /etc/init.d/ntp-client restart & fi --- PS: DynDNS should use a similar method, if you know the URL, please post a comment. (Something with members.dyndns.org, if I recall correctly) Show Sample Output


    5
    wget -q --user=<username> --password=<password> 'https://updates.opendns.com/nic/update?hostname=your_opendns_hostname&myip=your_ip' -O -
    Alanceil · 2009-06-22 18:08:42 24
  • This command gives you the number of lines of every file in the folder and its subfolders matching the search options specified in the find command. It also gives the total amount of lines of these files. The combination of print0 and files0-from options makes the whole command simple and efficient. Show Sample Output


    2
    find . -name "*.sql" -print0 | wc -l --files0-from=-
    vincentp · 2009-06-22 17:45:03 12
  • It works like a "tail -f" on several files. Use the number keys 0-9 to set a baseline in the numbered window. Pressing "b" let you scroll back in one of the windows.


    4
    multitail /var/log/messages /var/log/apache2/access.log /var/log/mail.info
    Neo23x0 · 2009-06-22 06:51:11 10
  • Uses logger in a while loop to log memory statistics frequently into the local syslog server.


    3
    while true; do { $(which logger) -p local4.notice `free -m | grep Mem`; sleep 60; } done &
    Neo23x0 · 2009-06-22 00:29:53 7
  • Command binds a set of commands to the F12 key. Feel free to alter the dashboard according to your own needs. How to find the key codes? Type read Then press the desired key (example: F5) ^[[15~ Try bind '"\e[15~"':"\"ssh su@ip-address\C-m""" or bind '"\e[16~"':"\"apachectl -k restart\C-m""" Show Sample Output


    18
    bind '"\e[24~"':"\"ps -elF;df -h;free -mt;netstat -lnpt;who -a\C-m"""
    Neo23x0 · 2009-06-21 23:57:20 81
  • !* is all of the arguments to the previous command rather than just the last one. This is useful in many situations. Here's a simple example: vi cd /stuff oops! [exit vi, twice] !* expands to: cd /stuff


    99
    !*
    Neo23x0 · 2009-06-21 17:58:01 20
  • This command securely erases all the unused blocks on a partition. The unused blocks are the "free space" on the partition. Some of these blocks will contain data from previously deleted files. You might want to use this if you are given access to an old computer and you do not know its provenance. The command could be used while booted from a LiveCD to clear freespace space on old HD. On modern Linux LiveCDs, the "ntfs-3g" system provides ReadWrite access to NTFS partitions thus enabling this method to also be used on Wind'ohs drives. NB depending on the size of the partition, this command could take a while to complete. Show Sample Output


    8
    # cd $partition; dd if=/dev/zero of=ShredUnusedBlocks bs=512M; shred -vzu ShredUnusedBlocks
    mpb · 2009-06-21 14:17:22 12

  • 3
    sudo sed 's/\o0/\n/g' "/proc/$(pidof -x firefox)/environ" ;# replace firefox
    plasticdoc · 2009-06-21 09:47:02 9
  • This command displays a clock on your terminal which updates the time every second. Press Ctrl-C to exit. A couple of variants: A little bit bigger text: watch -t -n1 "date +%T|figlet -f big" You can try other figlet fonts, too. Big sideways characters: watch -n 1 -t '/usr/games/banner -w 30 $(date +%M:%S)' This requires a particular version of banner and a 40-line terminal or you can adjust the width ("30" here). Show Sample Output


    48
    watch -t -n1 "date +%T|figlet"
    dennisw · 2009-06-21 01:02:37 39
  • sudo pmset -a hibernatemode 1 sets hiberate on. sudo pmset -a hibernatemode 0 sets hibernate off. from the pmset man page: 0001 (bit 0) enables hibernation; causes OS X to write memory state to hibernation image at sleep time. On wake (without bit 1 set) OS X will resume from the hibernation image. Bit 0 set (without bit 1 set) causes OS X to write memory state and immediately hibernate at sleep time. I often change my MacBook's sleep state. So I created a function for bash to make it a little easier. Usage: hibernate (on | off) "hibernate on" will set your laptop to hibernate if the lid is closed. "hibernate off" will set your laptop to sleep if the lid is closed. ### note : "proper" indentation isn't preserved on the website function hibernate() { case "${1}" in on) sudo pmset -a hibernatemode 1 echo Hibernate mode on. ;; off) sudo pmset -a hibernatemode 0 echo Hiberate mode off. ;; *) echo "I'm sorry Dave, but I can't do that." ;; esac } To make things easier, add the proper line in your /etc/sudoers file so that your user may invoke pmset without a password. Here's how mine looks: bwayne luna = NOPASSWD: /usr/bin/pmset Don't forget that you must edit sudoers with `sudo visudo` from Terminal.app, and not by another text editor. Sorry this is so Mac OS specific. Show Sample Output


    -1
    sudo pmset -a hibernatemode 1
    thebillywayne · 2009-06-20 22:52:10 8

  • 2
    svn status | grep '!' | sed 's/!/ /' | xargs svn del --force
    tarzantiger · 2009-06-20 13:01:07 6

  • 3
    mplayer dvdnav:// -dvd-device foo.img -mouse-movements
    dezza · 2009-06-19 23:03:04 7

  • 6
    unrar p -inul foo.rar|mplayer -
    dezza · 2009-06-19 22:40:01 7
  • The option -an disables audio recording, -f forces the use of video4linux for the input, -s sets the video to the size 320x240, -b sets the recording bitrate, -r sets the frame rate to 15fps, -i gives the input device, -vcodec sets the output format. Press Q to stop recording or you can specify the recording time with the -t option like -t 00:1:30


    3
    ffmpeg -an -f video4linux -s 320x240 -b 800k -r 15 -i /dev/v4l/video0 -vcodec mpeg4 myvideo.avi
    dcabanis · 2009-06-19 17:41:43 7
  • Encode video.avi into newvideo.avi using the libav codec to produce an MPEG4 file with a bitrate of 800


    1
    mencoder video.avi lavc -lavcopts vcodec=mpeg4:vbitrate=800 newvideo.avi
    dcabanis · 2009-06-19 17:30:46 7
  • video.avi is the resulting file. Press Ctrl+c to stop the recording. You can change the OVC option to another to record into a different format.


    1
    mencoder -tv device=/dev/video1 tv:// -ovc copy -o video.avi
    dcabanis · 2009-06-19 17:21:33 7
  • GNU Sed can 'address' between two regex, but it continues parsing through to the end of the file. This slight alteration causes it to terminate reading the input file once the STOP match is made. In my example I have included an extra '/START/d' as my 'start' marker line contains the 'stop' string (I'm extracting data between 'resets' and using the time stamp as the 'start'). My previous coding using grep is slightly faster near the end of the file, but overall (extracting all the reset cycles in turn) the new SED method is quicker and a lot neater. Show Sample Output


    3
    sed -n '/START/,${/STOP/q;p}'
    mungewell · 2009-06-19 15:27:36 11

  • -5
    ga
    miccaman · 2009-06-19 12:20:10 5
  • insert filename Normal mode: "%p Insert mode: %


    1
    :r! echo %
    miccaman · 2009-06-19 12:17:28 13
  • src: daily vim blog


    3
    :source ~/.vimrc
    miccaman · 2009-06-19 12:14:55 6

  • 2
    :set nomore :argdo %s/foo/bar/g | update
    miccaman · 2009-06-19 12:12:33 25
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Take a screenshot of the window the user clicks on and name the file the same as the window title
In general, this is actually not better than the "scrot -d4" command I'm listing it as an alternative to, so please don't vote it down for that. I'm adding this command because xwd (X window dumper) comes with X11, so it is already installed on your machine, whereas scrot probably is not. I've found xwd handy on boxen that I don't want to (or am not allowed to) install packages on. NOTE: The dd junk for renaming the file is completely optional. I just did that for fun and because it's interesting that xwd embeds the window title in its metadata. I probably should have just parsed the output from file(1) instead of cutting it out with dd(1), but this was more fun and less error prone. NOTE2: Many programs don't know what to do with an xwd format image file. You can convert it to something normal using NetPBM's xwdtopnm(1) or ImageMagick's convert(1). For example, this would work: "xwd | convert fd:0 foo.jpg". Of course, if you have ImageMagick already installed, you'd probably use import(1) instead of xwd. NOTE3: Xwd files can be viewed using the X Window UnDumper: "xwud <foo.xwd". ImageMagick and The GIMP can also read .xwd files. Strangely, eog(1) cannot. NOTE4: The sleep is not strictly necessary, I put it in there so that one has time to raise the window above any others before clicking on it.

follow the content of all files in a directory
The `-q' arg forces tail to not output the name of the current file

sort a JSON blob
For situations where you keep JSON in a VCS and you want your diffs to be sane, such as within a Chef configuration repo.

Change prompt to MS-DOS one (joke)

pass the output of some command to a new email in the default email client
This depends on 'stripansi' and 'urlencode' commands, which exist on my system as these aliases: $ alias stripansi='perl -ple "s/\033\[(?:\d*(?:;\d+)*)*m//g;"' $ alias urlencode='perl -MURI::Escape -ne "\$/=\"\"; print uri_escape \$_"' The `open` command handles URLs on a Mac. Substitute the equivalent for your system (perhaps gnome-open). I don't use system `mail`, so I have this aliased as `mail` and use it this way: $ git show head | mail

github push-ing behind draconian proxies!
If you are behind a restrictive proxy/firewall that blocks port 22 connections but allows SSL on 443 (like most do) then you can still push changes to your github repository. Your .ssh/config file should contain: Host * ForwardX11 no TCPKeepAlive yes ProtocolKeepAlives 30 ProxyCommand /usr/local/bin/proxytunnel -v -p -d %h:443 Host User git Hostname ssh.github.com ChallengeResponseAuthentication yes IdentityFile ~/.ssh/id_rsa IdentitiesOnly yes Basically proxytunnel "tunnels" your ssh connection through port 443. You could also use corkscrew or some other tunneling program that is available in your distro's repository. PS: I generally use "github.com" as the SSH-HOST so that urls of the kind git@github.com:USER/REPO.git work transparently :) You

add a gpg key to aptitute package manager in a ubuntu system
when we add a new package to a aptitude (the debian package manager) we need to add the gpg, otherwise it will show warning / error for missing key

Prepare a commandlinefu command.
This command will format your alias or function to a single line, trimming duplicate white space and newlines and inserting delimiter semi-colons, so it continues to work on a single line.

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"

Shortcut to find files with ease.
It looks for files that contains the given word as parameter. * case insensitive * matches files containing the given word.


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