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 31
  • 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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Rename files in batch

ROT13 using the tr command

Grab IP address on machine with multiple interfaces
Instead of hard-coding in a check to scrape info from ifconfig based on a specific interface, do it in a more portable way. This works really well if you switch between wired, wireless, bluetooth or even VPN connections. You can get your current IP in a script (since it'll be something like tun0 instead of eth0 or wlan1). This uses a well known public ip address 8.8.8.8, but it doesn't actually connect to it, it just shows you the route it would take.

change ownership en masse of files owned by a specific user, including files and directories with spaces
In the example, uid 0 is root. foo:foo are the user:group you want to make owner and group. '.' is the "current directory and below." -print0 and -0 indicate that filenames and directories "are terminated by a null character instead of by whitespace."

Tail postfix current maillog and grep for "criteria"
Tail curren postfix maillog.

Change host name
With sed you can replace strings on the fly.

Get HTTP status code with curl

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" }

Create multiple mp4 files using avidemux
Convert multiple files using avidemux. Version updated (thanks to the guys who helped me giving me hints about how to improve the command). Works with files whose name contains blank characters. One of the reasons why I love open source: everyone can take something "done" and improve it to make it better! If u have suggestions, please let me know.

Pack up some files into a tarball on a remote server without writing to the local filesystem
I recently found myself with a filesystem I couldn't write to and a bunch of files I had to get the hell out of dodge, preferably not one at a time. This command makes it possible to pack a bunch of files into a single archive and write it to a remote server.

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