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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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Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

All commands from sorted by
Terminal - All commands - 12,362 results
sed -n '/test/{/error\|critical\|warning/d;p}' somefile
2009-10-25 09:07:00
User: pipping
Functions: sed

That's what the sed command should've been, sorry.

dpkg-query -Wf '${Installed-Size}\t${Package}\n' | sort -n
git ls-files | xargs -n1 -d'\n' -i git-blame {} | perl -n -e '/\s\((.*?)\s[0-9]{4}/ && print "$1\n"' | sort -f | uniq -c -w3 | sort -r
2009-10-25 01:44:03
User: askedrelic
Functions: perl sort uniq xargs
Tags: statistics git

Figures out total line contribution per author for an entire GIT repo. Includes binary files, which kind of mess up the true count.

If crashes or takes too long, mess with the ls-file option at the start:

git ls-files -x "*pdf" -x "*psd" -x "*tif" to remove really random binary files

git ls-files "*.py" "*.html" "*.css" to only include specific file types

Based off my original SVN version: http://www.commandlinefu.com/commands/view/2787/prints-total-line-count-contribution-per-user-for-an-svn-repository

ssh -g -L 8080:localhost:80 root@$HOST
2009-10-24 20:56:00
User: kayowas
Functions: ssh

Forward connections to $HOSTNAME:8080 out to $HOST:80

nethogs -p eth0
2009-10-24 19:43:31

Nethogs is a useful tool for monitor bandwidth consumption by pid. Tested on Debian an CentOs

Convert Windows/DOS Text Files to Uni
sed -n /start_pattern/,/stop_pattern/p file.txt
truncate -s0 file
2009-10-24 16:31:03
User: pipping

The downside of output redirection is that you need permissions. So something like

> file

won't play nicely w/ sudo. You'd need to do something like

bash -c '> file'

instead, you could go w/

sudo truncate -s0 file
declare -F | sed 's/^declare -f //'
sed '/test/{/error\|critical\|warning/d}' somefile
2009-10-24 15:59:59
User: pipping
Functions: sed

If you wanted to do all in one command, you could go w/ sed instead

grep test somefile | grep -v -e error -e critical -e warning
2009-10-24 15:58:11
User: pipping
Functions: grep test

You can use -e to pass multiple patterns.

pwgen --alt-phonics --capitalize 9 10
2009-10-24 08:36:36
User: CafeNinja
Tags: Linux terminal

Produces secure passwords that satisfy most rules for secure passwords and can be customized for correct output as needed. See "man pwgen" for details.

genpass(){local i x y z h;h=${1:-8};x=({a..z} {A..Z} {0..9});for ((i=0;i<$h;i++));do y=${x[$((RANDOM%${#x[@]}))]};z=$z$y;done;echo $z ;}
2009-10-24 04:32:31
User: twfcc

make password randomly, default 8 chars, using bash3.X only, no external program.

genpass() { local h x y;h=${1:-8};x=( {a..z} {A..Z} {0..9} );y=$(echo ${x[@]} | tr ' ' '\n' | shuf -n$h | xargs);echo -e "${y// /}"; }
2009-10-24 04:05:42
User: twfcc
Functions: echo tr

make password randomly, default 8 char

grep 'test' somefile | grep -vE '(error|critical|warning)'
2009-10-23 23:21:36
User: zlemini
Functions: grep

Use multiple patterns with grep -v. So you can print all lines in a file except those containing the multiple patterns you specify.

curl -fs brandx.jp.sme 2&>1 > /dev/null || echo brandx.jp.sme ping failed | mail -ne -s'Server unavailable' [email protected]
2009-10-23 14:29:06
User: mccalni
Functions: echo mail ping
Tags: bash ping curl mail

Alternative to the ping check if your firewall blocks ping. Uses curl to get the landing page silently, or fail with an error code. You can probably do this with wget as well.

wmctrl -o 2560,0 ;sleep 2 ; echo "FIRE 001" | osd_cat -o 470 -s 8 -c red -d 10 -f -*-bitstream\ vera\ sans-*-*-*--250-*-*-*-*-*-*-* ; sleep 1; wmctrl -o 0,0
2009-10-23 10:00:51
User: m33600
Functions: echo sleep

Strip my code to:

wmctrl -o 0,0 # autorotates to the first face. In fact [0-1279],0

wmctrl - 1280,0 # goes to the second face

wmctrl -o 2560,0 # goes to the third face, and so on.

# Use multiples of the horizontal display resolution.

My example work for 1280x800 display, been 1280 the number of interest.

Tweak the number, try a biiiig one and see your cube spinning...

I put a complex example to show how fun things can be, even for my ademco and paradox alarm central network advisor interface xpto etc. It rotates two faces, print the alarm message, and goes back tho where it was.

Tested on BIGLINUX 4.2, equivalent to ubuntu LTS hardy.

Do not forget to activate 3D efects ( compiz cube )

export I=$(date +%s); watch -t -n 1 'T=$(date +%s);E=$(($T-$I));hours=$((E / 3600)) ; seconds=$((E % 3600)) ; minutes=$((seconds / 60)) ; seconds=$((seconds % 60)) ; echo $(printf "%02d:%02d:%02d" $hours $minutes $seconds) | toilet -f shadow'
2009-10-23 07:56:30
User: m33600
Functions: date echo export printf watch

already described on the other two versions, this one uses ascii characters on game style to display elapsed time.

export I=$(date +%s); watch -t -n 1 'T=$(date +%s);E=$(($T-$I));hours=$((E / 3600)) ; seconds=$((E % 3600)) ; minutes=$((seconds / 60)) ; seconds=$((seconds % 60)) ; echo $(printf "%02d:%02d:%02d" $hours $minutes $seconds) | osd_cat -o 20 -d 1 -p bottom'
2009-10-23 07:47:11
User: m33600
Functions: date echo export printf watch

Variation of the theme, this one blinks in low profile on top level of X, ie, it is visible, indeed small.

Try changing fonts and sizes of osd_cat

export I=$(date +%s); watch -t -n 1 'T=$(date +%s);E=$(($T-$I));hours=$((E / 3600)) ; seconds=$((E % 3600)) ; minutes=$((seconds / 60)) ; seconds=$((seconds % 60)) ; echo $(printf "%02d:%02d:%02d" $hours $minutes $seconds)'
2009-10-23 07:31:44
User: m33600
Functions: date echo export printf watch

Works on real time clock, unix time based, decrementing the actual time from initial time saved in an environment variable exported to child process inside watch

Shows elapsed time from start of script in hh:mm:ss format

Non afected by system slow down due to the use of date.

calc(){ awk "BEGIN{ print $* }" ;}
2009-10-23 06:03:07
User: twfcc
Functions: awk

simple function , floating point number is supported.

acpi -t | osd_cat -p bottom
2009-10-23 05:22:01
User: m33600
Functions: acpi

My firefox overheats my cpu, sometimes above 90 degrees Celsius ( hence the name? )

To keep an eye on temperature, I put this command inside KAlarm ( a kind of cron) to be repeated every minute, for 5 seconds, color red ( default for osd_cat).

Its pretty, ultra small, displays a micro 2 lines text on every desktop and over everything and do not steal focus or interrupt any task. I get the information passively, in the low profile bottom of the screen.

Of course you can use it inside a terminal. Just do it:

watch -n 60 'acpi -t | osd_cat -p bottom'

xset led 3
2009-10-23 00:25:56
User: m33600

Usefull as a light blink to remember events, mails, intrusions, etc... yet another output

Since nobody ever uses the scroll lock function...

Usefull to interface a linux system with some hardware, for example, opto interfacing the keyboard led to a relay to remotely reset, etc. ( a simple LDR glued over the LED will do the trick )

xset led 3 turns on the third led, ie, Scroll lock

xset -led 3 turns it off

xset led 1 turns on Numerical Lock led ( doesn t work on all computer )

xset led 2 turns on Caps Lock led ( idem )

Using it as a reset watchdog, the relay expected light pulses. Shall the computer hangs, the relay releases and reset the machine ( discharge of a capacitor ) ;-)

declare -f [ function_name ]
set | fgrep " ()"
2009-10-22 17:48:54
User: haivu
Functions: fgrep set

If you issue the "set" command, you'll see a list of variables and functions. This command displays just those functions' names.