All commands (14,187)

  • Make alias pemanent fast

    Simple function to permanently add an alias to your profile. Tested on bash and Ksh, bash version above. Here is the ksh version: PERMA () { print "$@" >> ~/.profile; } Sample usage: PERMA alias la='ls -a'


    2
    PERMA () { echo "$@" >> ~/.bashrc; }
    zlemini · 2009-09-28 16:03:24 9
  • Perform a reverse DNS lookup

    Performs a reverse DNS lookup, variants include: nslookup 74.125.45.100 or: host 74.125.45.100 Show Sample Output


    4
    dig -x 74.125.45.100
    postrational · 2009-09-28 15:13:34 3
  • Change user, assume environment, stay in current dir

    I've used this a number of times troubleshooting user permissions. Instead of just 'su - user' you can throw another hyphen and stay in the original directory. Show Sample Output


    13
    su -- user
    matthewdavis · 2009-09-28 04:23:43 7
  • Makes a project directory, unless it exists; changes into the dir, and creates an empty git repository, all in one command

    gitstart ~/path/to/dir Initialized empty Git repository in /home/user/path/to/dir/.git/


    0
    gitstart () { if ! [[ -d "$@" ]]; then mkdir -p "$@" && cd "$@" && git init; else cd "$@" && git init; fi }
    xyz · 2009-09-28 01:12:32 3
  • Matrix Style

    I like the fact the Patola's version uses only ones and zeros, but I also like the sparse output of the other versions. This one combines both of those features and eliminates some unnecessary cruft. You can vary the sparseness by changing "$(($RANDOM % 5))" to another number. The number in this term "$(($RANDOM % 4))" controls how frequently the numbers are output bold.


    21
    echo -e "\e[32m"; while :; do for i in {1..16}; do r="$(($RANDOM % 2))"; if [[ $(($RANDOM % 5)) == 1 ]]; then if [[ $(($RANDOM % 4)) == 1 ]]; then v+="\e[1m $r "; else v+="\e[2m $r "; fi; else v+=" "; fi; done; echo -e "$v"; v=""; done
    dennisw · 2009-09-27 15:30:38 16
  • create pdf files from text files or stdout.


    7
    enscript jrandom.txt -o - | ps2pdf - ~/tmp/jrandom.pdf (from file) or: ls | enscript -o - | ps2pdf - ~/tmp/ls.pdf (from stdout)
    bartonski · 2009-09-27 15:15:16 6
  • Go get those photos from a Picasa album


    2
    wget 'link of a Picasa WebAlbum' -O - |perl -e'while(<>){while(s/"media":{"content":\[{"url":"(.+?\.JPG)//){print "$1\n"}}' |wget -w1 -i -
    aciancone · 2009-09-27 14:36:27 7
  • convert .rpm to .deb using alien

    convert to debian package file (deb) a redhat package file (rpm) , then you can install it by using dpkg , require alien package ( sudo apt-get install alien first ) Show Sample Output


    -5
    sudo alien --to-deb Your_PackAge.rpm
    eastwind · 2009-09-27 13:49:07 5
  • Disable beep sound from your computer

    This command will disable the beep sound from the PC speaker.


    5
    echo "blacklist pcspkr"|sudo tee -a /etc/modprobe.d/blacklist.conf
    sliceoflinux · 2009-09-27 11:42:47 5
  • save date and time for each command in history

    Date-time format: YYYY-MM-DD HH:MM:SS Show Sample Output


    7
    export HISTTIMEFORMAT='%F %T '
    postrational · 2009-09-26 17:13:23 7
  • Install a LAMP server in a Debian based distribution

    The execution of this command will install a LAMP server (Linux, Apache, MySQL and PHP) in a Debian based distribution. For example, in Ubuntu.


    5
    sudo tasksel install lamp-server
    sliceoflinux · 2009-09-26 08:15:03 8
  • Download a TiVo Show

    Download the last show on your TiVo DVR. Replace $MAK with your MAK see https://www3.tivo.com/tivo-mma/showmakey.do Replace $tivo with your TiVo's IP


    0
    curl -s -c /tmp/cookie -k -u tivo:$MAK --digest "$(curl -s -c /tmp/cookie -k -u tivo:$MAK --digest https://$tivo/nowplaying/index.html | sed 's;.*<a href="\([^"]*\)">Download MPEG-PS</a>.*;\1;' | sed 's|\&amp;|\&|')" | tivodecode -m $MAK -- - > tivo.mpg
    matthewbauer · 2009-09-26 03:00:46 5
  • Log a command's votes

    Log a command's votes, then run: gnuplot -persist <(echo "plot 'votes' with lines")


    0
    while true; do curl -s http://www.commandlinefu.com/commands/view/3643/log-a-commands-votes | grep 'id="num-votes-' | sed 's;.*id="num-votes-[0-9]*">\([0-9\-]*\)</div>;\1;' >> votes; sleep 10; done
    matthewbauer · 2009-09-26 00:55:24 44
  • save date and time for each command in history

    for the change stay in your history file , export command by writing it into your .bashrc Show Sample Output


    7
    export HISTTIMEFORMAT="%h/%d-%H:%M:%S "
    eastwind · 2009-09-25 22:42:28 7
  • Rip DVD to YouTube ready MPEG-4 AVI file using mencoder

    Rip DVD to YouTube ready AVI file, using MPEG-4 video codec and MP3 audio codec. Resizes to 320x240 and deinterlaces as needed.


    4
    mencoder -oac mp3lame -lameopts cbr=128 -ovc lavc -lavcopts vcodec=mpeg4 -ffourcc xvid -vf scale=320:-2,expand=:240:::1 -o output.avi dvd://0
    ivalladt · 2009-09-25 19:29:25 3
  • Display summary of git commit ids and messages for a given branch

    In color. Additionally you may define in your ~/.gitconfig and run it just as 'git one': one = log --pretty='format:%Cgreen%H %Cred%ai %Creset- %s'


    1
    git log --pretty='format:%Cgreen%H %Cred%ai %Creset- %s'
    levenbrech · 2009-09-25 19:18:37 35
  • Create a single-use TCP proxy with debug output to stderr

    or you can add "-x" to get a typical hexdump like output Show Sample Output


    5
    socat -v tcp4-l:<port> tcp4:<host>:<port>
    sitaram · 2009-09-25 17:10:16 4
  • Get all members from one AD group and put them in another AD group

    Interacting with Active Directory to add users from one group to another group. This prevents from having to deal with long DNs and copying, pasting problems. It executes once per returned object.


    -3
    for /F "DELIMS=""" %i in ('dsquery group -name SourceGroupName ^| dsget group -members') do dsquery group -name TargetGroupName | dsmod group -addmbr %i
    miketheman · 2009-09-25 16:32:33 10
  • List Network Tools in Linux

    Get all the networking related commands for your distro Show Sample Output


    13
    apropos network |more
    shaiss · 2009-09-25 15:05:33 12
  • Detect if we are running on a VMware virtual machine

    If you run this command on a VMWare Virtual Machine, it will return the string "VMware Virtual Platform". If you run it on a physical machine, it will return nothing. Useful for having a script determine if it's running on a VM or not. Of course, you must have dmidecode installed for this to work. Try it this way in a script: ISVM=$(dmidecode | awk '/VMware Virtual Platform/ {print $3,$4,$5}') Then test if $ISVM has text in it, or is blank.


    7
    dmidecode | awk '/VMware Virtual Platform/ {print $3,$4,$5}'
    SuperFly · 2009-09-25 14:46:35 13
  • Colorized grep in less


    0
    ack --pager='less -r'
    unixmonkey5780 · 2009-09-25 13:01:58 3
  • Create/open/use encrypted directory

    Create/open/use an encrypted directory encfs needs to be installed During creation easiest to use default values The encrypted files will be in ~/.crypt and you will work as usual in ~/crypt To close the encrypted directory run: fusermount -u ~/crypt When you switch off the computer the encrypted directory will be automatically closed This example uses /home/user/crypt as encrypted directory I use ubuntu linux 8.04 and I am also the creator of www.minihowto.org


    8
    encfs ~/.crypt ~/crypt
    bkn390 · 2009-09-25 10:13:39 5
  • Install a deb package

    Install a deb package you have downloaded (synaptic has to be closed). (dpkg-dev needs to be installed) After that you may have to run following: sudo apt-get install -f (that should fix any dependency problems) I am using ubuntu linux


    -7
    sudo dpkg -i packagename.deb
    bkn390 · 2009-09-25 09:54:04 13
  • Remove blank lines from a file using grep and save output to new file


    30
    grep . filename > newfilename
    alvinx · 2009-09-25 09:25:34 17
  • Backup all MySQL Databases to individual files

    No need to loop when we have `xargs`. The sed command filters out the first line of `show databases` output, which is always "Database".


    5
    mysql -e 'show databases' | sed -n '2,$p' | xargs -I DB 'mysqldump DB > DB.sql'
    mislav · 2009-09-25 08:43:06 9
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Redirect incoming traffic to SSH, from a port of your choosing
Stuck behind a restrictive firewall at work, but really jonesing to putty home to your linux box for some colossal cave? Goodness knows I was...but the firewall at work blocked all outbound connections except for ports 80 and 443. (Those were wide open for outbound connections.) So now I putty over port 443 and have my linux box redirect it to port 22 (the SSH port) before it routes it internally. So, my specific command would be: $iptables -t nat -A PREROUTING -p tcp --dport 443 -j REDIRECT --to-ports 22 Note that I use -A to append this command to the end of the chain. You could replace that with -I to insert it at the beginning (or at a specific rulenum). My linux box is running slackware, with a kernel from circa 2001. Hopefully the mechanics of iptables haven't changed since then. The command is untested under any other distros or less outdated kernels. Of course, the command should be easy enough to adapt to whatever service on your linux box you're trying to reach by changing the numbers (and possibly changing tcp to udp, or whatever). Between putty and psftp, however, I'm good to go for hours of time-killing.

Simple colourized JSON formatting for BASH
Leave out pygmentize or `pip install pygments` first.

Protect your eye
Redshift will adjust the color temperature and protects eye at night -b : will adjust the brightness

Find 10 largest files in git history

Interactively build regular expressions
txt2regex can be interactive or noninteractive and generates regular expressions for a variety of dialects based on user input. In interactive mode, the regex string builds as you select menu options. The sample output here is from noninteractive mode, try running it standalone and see for yourself. It's written in bash and is available as the 'txt2regex' package at least under debian/ubuntu.

check open ports
Tested in Linux and OSX

Block an IP address from connecting to a server
This appends (-A) a new rule to the INPUT chain, which specifies to drop all packets from a source (-s) IP address.

adjust laptop display hardware brightness [non root]

use jq to validate and pretty-print json output
the `jq` tool can also be used do validate json files and pretty print output `cat file.json | jq` available on several platforms, including newer debian-based systems via `#sudo apt install jq`, mac via `brew install jq`, and from source https://stedolan.github.io/jq/download/

Filter the output of a file continously using tail and grep
The OPs solution will work, however on some systems (bsd), grep will not filter the data, unless the --line-buffered option is enabled.

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