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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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Commands by totti from sorted by
Terminal - Commands by totti - 87 results
pmi action suspend
export HISTFILESIZE=99999
2013-01-02 09:25:06
User: totti
Functions: export

set how many commands to keep in history

Default is 500

Saved in /home/$USER/.bash_history

Add this to /home/$USER/.bashrc



sed '/foo/ s/foo/foobar/g' <filename>
2013-01-02 08:52:44
User: totti
Functions: sed
Tags: sed file optimize

Use optimized sed to big file/stream to reduce execution time


sed '/foo/ s/foo/foobar/g' <filename>

insted of sed

's/foo/foobar/g' <filename>
ls -l /proc/*/fd/* | grep 'deleted'| grep "\/proc.*\file-name-part"
2012-09-13 09:54:16
User: totti
Functions: grep ls

Accidentally deleted some file while used by a program ? (Eg: a song)

Use this command to find the file handle and recover using

cp /proc/pid/fd/filehandle /new/recoverd-file.ext
aspectRatio () { for i in `seq 1 1000 `; do awk "BEGIN {print $1/$i, $2/$i}"; done |grep -v "\."; }
2012-03-07 06:22:25
User: totti
Functions: awk grep

EG: aspectRatio 1920 1200

For display a image in full screen it should be in any of the resolution obtained from the output. So resize an image to any of it and you can display it in full screen

For general aspect ratio :

aspectRatio () { for i in `seq 1 1000 `; do awk "BEGIN {print $1/$i, $2/$i}"; done |grep -v "\." |tail -1; }
redshiftgui -o -b 0.5
2012-02-26 16:10:02
User: totti

Redshift will adjust the color temperature and protects eye at night

-b : will adjust the brightness

identify image.jpg |grep -o "[[:digit:]]*x[[:digit:]]*" |tail -1
grep -r <searchterm> *
showkey -a
xdotool getmouselocation
wmctrl -o 100,0
2012-01-19 14:36:20
User: totti
Tags: switc

For a demo try

wmctrl -o 100,0; sleep 3; wmctrl -o 1500,0; sleep 3; wmctrl -o 3000,0; sleep 3; wmctrl -o 4500,0;


wmctrl -o <width x Number>,0;

to switch to that workspace

cryptmount -m <name>
2012-01-17 18:02:47
User: totti

In order to create a new encrypted filing system managed by cryptmount,

you can use the supplied 'cryptmount-setup' program, which can be used

by the superuser to interactively configure a basic setup.

Alternatively, suppose that we wish to setup a new encrypted filing

system, that will have a target-name of "opaque". If we have a free

disk partition available, say /dev/hdb63, then we can use this directly

to store the encrypted filing system. Alternatively, if we want to

store the encrypted filing system within an ordinary file, we need to

create space using a recipe such as:

dd if=/dev/zero of=/home/opaque.fs bs=1M count=512


cryptmount --generate-key 32 opaque


cryptmount --prepare opaque


mke2fs /dev/mapper/opaque


cryptmount --release opaque


mkdir /home/crypt


cryptmount -m opaque


cryptmount -u opaque

For detail see sample output

makeself <archive_dir> <file_name> <label>
2012-01-10 18:08:50
User: totti

Used by virtualbox and others to create '.run' file.

cat <file> > /dev/null
2011-11-12 15:45:27
User: totti
Functions: cat
Tags: ram file cache

Best result when file size less than half of RAM size

stat --format "%s" <file>
curl http://www.commandlinefu.com/commands/browse/sort-by-votes/plaintext/[0-9000:25] | grep -vE "_curl_|\.com by David" > clf-ALL.txt
2011-11-08 12:19:48
User: totti
Functions: grep

Faster then other method using wget

For obtain all commands use

nu=`curl http://www.commandlinefu.com/commands/browse |grep -o "Terminal - All commands -.*results$" | grep -oE "[[:digit:],]{4,}" | sed 's/,//'`; curl http://www.commandlinefu.com/commands/browse/sort-by-votes/plaintext/[0-"$nu":25] | grep -vE "_curl_|\.com by David" > clf-ALL.txt

For more version specific

nu=`curl http://www.commandlinefu.com/commands/browse |grep -o "Terminal - All commands -.*results$" | grep -oE "[[:digit:],]{4,}" | sed 's/,//'`; curl http://www.commandlinefu.com/commands/browse/sort-by-votes/plaintext/[0-"$nu":25] | grep -vE "_curl_|\.com by David" > clf-ALL_"$nu".txt

Also download dirctly from my dropbox

My drop box invitaion link is http://db.tt/sRdJWvQq . Use it and get free 2.5 GB space.

totem-video-thumbnailer -pg 25 in_video out_png
ffmpeg -ss 5 -i video.avi -vframes 1 -s 320x240 thumb.jpg
2011-10-31 17:19:33
User: totti

Faster thumbnail creation than '-itsoffset'

ffmpeg -itsoffset -4 -i test.avi -vcodec mjpeg -vframes 1 -an -f rawvideo -s 320x240 test.jpg
read -d ""
2011-10-25 18:44:11
User: totti
Functions: read

Handle any bad named file which contains ",',\n,\b,\t,` etc

Store the file name as null character separated list

find . -print0 >name.lst

and retrieve it using

read -r -d ""


find . -print0 >name.lst; cat name.lst| while IFS="" read -r -d "" file; do ls -l "$file"; done
find . ! -name "$(printf '*[\001-\037\177]*')"
echo "export LESS_TERMCAP_mb=$'\E[01;31m'" >> ~/.bashrc
2011-10-20 17:34:14
User: totti
Functions: echo
Tags: man less color

Add the followin to ~/.bashrc


export LESS_TERMCAP_mb=$'\E[01;31m'

export LESS_TERMCAP_md=$'\E[01;37m'

export LESS_TERMCAP_me=$'\E[0m'

export LESS_TERMCAP_se=$'\E[0m'

export LESS_TERMCAP_so=$'\E[01;44;33m'

export LESS_TERMCAP_ue=$'\E[0m'

export LESS_TERMCAP_us=$'\E[01;32m'

filext () { echo ${1##*.}; }
echo "root=/dev/sda7" > /proc/param.conf
2011-09-27 18:06:53
User: totti
Functions: echo

Then exit from the shell.


some time need to exit twice

exit exit

Now the OS will boot with the new parameters.

sudo grub-install --root-directory=/media/ubuntu /dev/sda
2011-09-27 17:51:56
User: totti
Functions: sudo
Tags: grub boot fix

From live CD mount(open) the Ubuntu installed drive.

Copy the location (press Ctrl+l, Ctrl+c ) eg: /media/ubuntuuuu

Open terminal (Apllication->accessories->terminal)

Type this:

sudo grub-install --root-directory=/media/ubuntuuuu /dev/sda

(replace /media/ubuntuuuu with what u got (ie paste))

Will show success message. Now reboot

while read line; do echo $line; done <<< "$var"
2011-09-22 16:53:32
User: totti
Functions: echo read

Consider the following simple situation [ reading something using while and read ]

[See script 1 in sample output]


The variable var is assigned with "nullll" at first. Inside the while loop [piped while] it is assigned with "whillleeee". [Onlly 2 assignments stmts]. Outside the loop the last assigned value for "var" [and no variable] inside the while can't be accessed [Due to pipe, var is executed in a sub shell].

In these type of situation variables can be accessed by modifying as follows.

[See script 2 in sample output]


Vary helpful when reading a set of items, say file names, stored on a file [or variable] to an array an use it later.

Is there any other way 2 access variables inside and outside the loop ??