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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

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Terminal - All commands - 12,394 results
~<press tab twice>
hexdump -e '90/1 "%_p" "\n"' /dev/mem | less
2009-05-12 16:20:57
User: copremesis
Functions: hexdump

see what's in your memory right now... sometimes you find passwords, account numbers and url's that were recently used. Anyone have a safe command to clear the memory without rebooting?

2009-05-12 14:36:42
User: fritz_monroe
Functions: export

History usually only gives the command number and the command. This will add a timestamp to the history file.

Note: this will only put the correct timestamp on commands used after the export is done. You may want to put this in your .bashrc

kudzu -p
2009-05-12 10:34:59
Functions: kudzu

Kudzu is available on CentOS, used for configuring and detecting new hardware device installed, is also usefull for device listing.

tcs -f 8859-1 -t utf /some/file
2009-05-12 10:13:02
User: michauko
Tags: utf iso

I use it sometimes when I work on a french file transferred from a windows XP to a Debian-UTF8 system. Those are not correctly displayed: ? ? ? and so on

man tcs # for all charsets
egrep -v "^$|^[[:space:]]*#" /etc/some/file
2009-05-12 07:14:48
User: michauko
Functions: egrep
Tags: egrep

Shows a file without comments (at least those starting by #)

- removes empty lines

- removes lines starting by # or "some spaces/tabs then #'"

Useful when you want to quickly see what you have to customize on a freshly installed application without reading the comments that sometimes are a full 1000 lines documentation :)

While posting, I saw this http://www.commandlinefu.com/commands/view/1041/display-contents-of-a-file-wo-any-comments-or-blank-lines

But it's dirty and incomplete, to my mind

My original goal was to remove lines like "\t*#" but I can't figure out how to do a egrep '\t' on a command-line. Two workarounds if needed:

egrep -v 'press control + V then TAB then #' /your/file


egrep -v -f some_file /your/file #where some_file contains what you want to exclude, example a really inserted TAB
grep -i '<searchTerm>\|<someOtherSearchTerm>' <someFileName>
2009-05-11 23:05:54
User: scifisamurai
Functions: grep

This is a simple but useful command to search for multiple terms in a file at once. This prevents you from having to do mutliple grep's of the same file.

fold -s -w 90 file.txt
2009-05-11 23:00:25
User: vincentp
Functions: fold

wraps text lines at the specified width (90 here).

-s option is to force to wrap on blank characters

-b count bytes instead of columns

echo 2006-10-10 | grep -c '^[0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9]$'
2009-05-11 22:18:43
User: rez0r
Functions: echo grep

Quick and easy way of validating a date format of yyyy-mm-dd and returning a boolean, the regex can easily be upgraded to handle "in betweens" for mm dd or to validate other types of strings, ex. ip address.

Boolean output could easily be piped into a condition for a more complete one-liner.

growisofs -M /dev/dvd -J -r "directory name with files to add to DVD"
2009-05-11 12:44:32
User: vleolml

replace "directory name with files to add to DVD" with actual directory containing files you want to add to growable DVD

growisofs -Z /dev/dvd -J -r "directory name to burn on DVD"
2009-05-11 12:42:18
User: vleolml

replace "directory name to burn on DVD" with actual directory name that you want to copy on DVD

ifconfig eth0 hw ether 00:11:22:33:44:55
dd if=/dev/mem of=file.dump bs=1024 skip=0 count=1
function echox { echo `tput cup $(($(tput lines))) $(( ($(tput cols) - $(echo "${#1}"))/2 ))`"$1"`tput cup $(tput lines) $(( $(tput cols)-1 ))`; }
2009-05-10 23:24:49
Functions: echo tput
function echox { echo `tput cup $(($(tput lines))) $(( ($(tput cols) - $(echo "${#1}"))/2 ))`"$1"`tput cup $(tput lines) $(( $(tput cols)-1 ))`; }

echox prints given argument on bottom line center screen in terminal

function echoxy { echo `tput cup $(($(tput lines)/2)) $(( ($(tput cols) - $(echo "${#1}"))/2))`"$1"`tput cup $(tput lines) $(( $(tput cols)-1 ))`; }

exhoxy prints given argument center screen

function echos { echo `tput cup $(($(tput lines)-2)) $(($(tput cols)-$(echo ${#1})))&&tput sc`"$1"`tput cup $(($(tput lines)-2)) 0 && tput rc`; } while [ 1 ]; do echos "`date`"; done

echos prints date and time on second from last line (used as status message)

you can easily use these functions by placing them in your .bashrc file, make sure to source your .bashrc once you do

echo '{"json":"obj"}' | python -m simplejson.tool
2009-05-10 13:58:05
User: azeey
Functions: echo python
Tags: python json

You can use a site like http://www.jsonlint.com/ or use the command line to validate your long and complex json data. This is part of the simplejson package for python http://undefined.org/python/#simplejson.

Wrong json expression example:

echo '{ 1.2:3.4}' | python -m simplejson.tool

Expecting property name: line 1 column 2 (char 2)

find / \( -name "*.log" -o -name "*.mylogs" \) -exec ls -lrt {} \; | sort -k6,8 | head -n1 | cut -d" " -f8- | tr -d '\n' | xargs -0 rm
2009-05-10 10:45:48
User: ghazz
Functions: cut find head ls sort tr xargs

This works on my ubuntu/debian machines.

I suspect other distros need some tweaking of sort and cut.

I am sure someone could provide a shorter/faster version.

for i in `seq -w 1600` ; do links -dump http://www.robsjokes.com/$i/index.html | sed '/Random Joke/,/Next Joke/!d' | sed '/^$/,/^$/!d' >> ~/temp/Rob.jokes ; echo '%' >> ~/temp/Rob.jokes ; done
perl -lane 'print "$F[0]:$F[1]:$F[2]"' myfile
2009-05-09 21:30:55
Functions: perl

Consider this line :

random perl language this make possible is

is possible to rearrange words with $F perl variable and word index, starting from 0.

2009-05-09 20:33:27

wmwave is part of wmwave package, when launched display a small wireless link monitor on your desktop with noise, level and link power.

setfont cybercafe
2009-05-09 20:08:47

setfont load vga console font. The default font directory is usually in /lib/kbd/consolefonts. Setfont is part of kbd package. Tested on CentOS.

ethstatus -i eth0
2009-05-09 19:33:39

ethstatus part of ethstatus package, is a consolle based monitor for network interfaces. Nicely display on screen a real time summary about bandwidth, speed and packets.

echo $?
2009-05-09 17:32:23
Functions: echo

The variable ? contain the last exit status of a command, it can be printed for troubleshooting purpose.

find ~user/ -name "*~" -exec rm {} \;
2009-05-09 12:55:47
Functions: find rm

I use this simple command for remove all backup files generated usually by editors like Vim and Emacs.