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 36
  • 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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When was your OS installed?
Show time and date when you installed your OS.

Look for English words in /dev/urandom
Little faster alternative.

Convert from octal format to umask
Umask is obtained subtracting 7 from each cypher of octal format. I store octal perm format in an array,then for each element of array I subtract 7. The result is the umask.

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"

Emptying a text file in one shot
% = buffer d = delete

Efficient count files in directory (no recursion)
$ time perl -e 'if(opendir D,"."){@a=readdir D;print $#a - 1,"\n"}' 205413 real 0m0.497s user 0m0.220s sys 0m0.268s $ time { ls |wc -l; } 205413 real 0m3.776s user 0m3.340s sys 0m0.424s ********* ** EDIT: turns out this perl liner is mostly masturbation. this is slightly faster: $ find . -maxdepth 1 | wc -l sh-3.2$ time { find . -maxdepth 1|wc -l; } 205414 real 0m0.456s user 0m0.116s sys 0m0.328s ** EDIT: now a slightly faster perl version $ perl -e 'if(opendir D,"."){++$c foreach readdir D}print $c-1,"\n"' sh-3.2$ time perl -e 'if(opendir D,"."){++$c foreach readdir D}print $c-1,"\n"' 205414 real 0m0.415s user 0m0.176s sys 0m0.232s

Find name of package which installed a given shell command
Some command names are very different from the name of the package that installed them. Sometimes, you may want to find out the name of the package that provided a command on a system, so that you can install it on another system.

lazy SQL QUERYING
This is regarding the command 8263 using an alias to fill in command line options for psql. You can actually just type 'psql'. In order for that to work, you want to set environment variables PGDATABASE, PGHOST, PGUSER, and (except you're using the default) PGPORT. Also, you can add a line "host:port:dbname:user:password" (asterisk ok in some columns) to your ~/.pgpass file. Finally, if you don't like the aligned columns, you can add the line "\pset format unaligned" to your ~/.psqlrc file.

Count accesses per domain
count the times a domain appears on a file which lines are URLs in the form http://domain/resource.

Find all clients connected to HTTP or HTTPS ports
It finds, specifically, the connections to the HTTP and HTTPS ports as source ports. You can check for destination ports as well.

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