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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(Debian/Ubuntu) Discover what package a file belongs to
Works similar to dpkg -S, but uses the locatedb and is thus inarguably a lot faster - if the locatedb is current.

Debug pytest failures in the terminal
pudb is an ncurses debugger. This command will allow interactive debugging of test failures in pytest using pudb.

Downsample mp3s to 128K
This will lower the quality of mp3 files, but is necessary to play them on some mobile devices.

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Find last modified files in a directory and its subdirectories
Goes through all files in the directory specified, uses `stat` to print out last modification time, then sorts numerically in reverse, then uses cut to remove the modified epoch timestamp and finally head to only output the last 10 modified files. Note that on a Mac `stat` won't work like this, you'll need to use either: $ find . -type f -print0 | xargs -0 stat -f '%m%t%Sm %12z %N' | sort -nr | cut -f2- | head or alternatively do a `brew install coreutils` and then replace `stat` with `gstat` in the original command.

ssh to machine behind shared NAT
Useful to get network access to a machine behind shared IP NAT. Assumes you have an accessible jump host and physical console or drac/ilo/lom etc access to run the command. Run the command on the host behind NAT then ssh connect to your jump host on port 2222. That connection to the jump host will be forwarded to the hidden machine. Note: Some older versions of ssh do not acknowledge the bind address (0.0.0.0 in the example) and will only listen on the loopback address.

Calculates the date 2 weeks ago from Saturday the specified format.
Good for automating reports that need to run from between two dates.

Download Youtube video with wget!
Nothing special required, just wget, sed & tr!

revert a committed change in SVN
This command can be used to revert a particular changeset in the local copy. I find this useful because I frequently import files into the wrong directory. After the import it says "Committed revision 123" or similar. to revert this change in the working copy do: svn merge -c -123 . (don't forget the .) and then commit.

Watch active calls on an Asterisk PBX
Show active calls as the happen on an Asterisk server. Note that the Asterisk command (in single quotes) is formatted for Asterisk 1.6. Use the -n flag on the watch command to modify the refresh period (in seconds - default is 2 seconds).


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