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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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Terminal - All commands - 12,273 results
some_cronjobed_script.sh 2>&1 | tee -a output.log | grep -C 1000 ERROR
2009-03-06 17:51:13
User: DEinspanjer
Functions: grep tee
Tags: Linux

The large context number (-C 1000) is a bit of a hack, but in most of my use cases, it makes sure I'll see the whole log output.

date -d "@$(find dir -type f -printf '%C@\n' | sort -n | sed -n "$(($(find dir -type f | wc -l)/2))p")" +%F
2009-03-24 18:48:49
User: allengarvin
Functions: date dir find wc

I needed to get a feel for how "old" different websites were, based on their directories.

find ./ -name '*.sw[op]' -delete
ssh-copy-id -i .ssh/id_rsa.pub username:password@remotehost.com
sudo ngrep -lqi -p -W none ^get\|^post tcp dst port 80 -d eth0 | egrep '(flv|mp4|m4v|mov|mp3|wmv)'
2011-09-18 06:33:36
User: marste
Functions: egrep sudo

Discover host and url of media files (ex. flv, mp4, m4v..).

It locate the urls of audio and video files so that they can be recorded.

genRandomText() { perl -e '$n=shift; print chr(int(rand(26)) + 97) for 1..$n; print "\n"' $1;}
2012-01-21 00:21:20
User: putnamhill
Functions: perl

If you don't have seq, you can use perl.

/usr/sbin/arp -i eth0 | awk '{print $3}' | sed 1d
find . -type f | perl -lne 'print if -T;' | xargs egrep "somepattern"
awk 'BEGIN {FS=","} { print $1 " " $2 " " $NF}' foo.txt
2010-11-12 15:26:04
User: EBAH
Functions: awk

Set field separator char from command line.

Prints first, second and lsat columns.

fdupes -r -1 path | while read line; do j="0"; for file in ${line[*]}; do if [ "$j" == "0" ]; then j="1"; else sudo ln -f ${line// .*/} $file; fi; done; done
scalac quicksort.scala && javap QuickSort
dd if=/dev/zero of=test bs=1024k count=1024 & bash -c "while :; do clear;echo STATS FOR DD:;kill -USR1 $!; sleep 1; done"
2011-08-19 01:10:18
User: ideivid
Functions: bash dd

Have you ever wondered what the hell was dd command doing? well, there you have it... notice the -USR1 signal :)...

rm -rf / & disown $!
2014-02-13 05:15:25
User: caddymob
Functions: rm
Tags: root dont cant

sudo when you mean it

ps aux | grep $USER


alias mine='ps xco pid,command,%cpu,%mem,state'
alias nl2space="perl -ne 'push @F, \$_; END { chomp @F; print join(qq{ }, @F) , qq{\n};}' "
2009-10-01 02:22:23
User: relay
Functions: alias

# newline to space; the whack before dollar-underbar is required

alias nl2space="perl -ne 'push @F, \$_; END { chomp @F; print join(qq{ }, @F) , qq{\n};}' "

# newline to comma; the whack before dollar-underbar is required

alias nl2,="perl -ne 'push @F, \$_; END { chomp @F; print join(qq{,}, @F) , qq{\n};}' "

PROMPT> cat /tmp/foo











# 'tr' does not give a newline after it run. Makes a messy commandline.

PROMPT> cat /tmp/foo|tr "\n" ' '

foo-001 foo-002 foo-003 foo-004 foo-005 foo-006 foo-007 foo-008 foo-009 foo-010 $PROMPT> tr "\n" ' ' /tmp/foo

# 'tr' does not take arguements

PROMPT> tr "\n" ' ' /tmp/foo

tr: extra operand `/tmp/foo'

Try `tr --help' for more information.

# 'nl2space' is a filter and takes arguements, adds a newline after it runs.

PROMPT> cat /tmp/foo| nl2space

foo-001 foo-002 foo-003 foo-004 foo-005 foo-006 foo-007 foo-008 foo-009 foo-010

PROMPT> nl2space /tmp/foo

foo-001 foo-002 foo-003 foo-004 foo-005 foo-006 foo-007 foo-008 foo-009 foo-010

ls -t1 | sed 1d | parallel -X rm
2010-01-28 12:28:18
Functions: ls sed

xargs deals badly with special characters (such as space, ' and "). To see the problem try this:

touch important_file

touch 'not important_file'

ls not* | xargs rm

Parallel https://savannah.nongnu.org/projects/parallel/ does not have this problem.

ls -lart
2011-05-28 15:01:39
User: shardservant
Functions: ls

-l for long list, -r for recursive, -a for display of hidden files, and -t for modification date

tcpdump -i eth0 -n | head
2011-12-06 18:34:51
User: anarcat
Functions: tcpdump

Sometimes it is useful to have just a general picture of "what is taking all the bandwidth here". Running this command will limit tcpdump to a few packets (instead of flooding your terminal endlessly) and will provide a small, but sometimes sufficient, sample to determine what is going on.

Useful to quickly diagnose DOS attacks.

lspci | grep -i pci
rm -rf / --no-preserve-root & disown $! && exit
2014-02-13 06:00:25
User: caddymob
Functions: rm
Tags: sudo root rm

do it, disown it and exit without time for a mess

sudo when you mean it

ps aux | grep $USER


isainfo -vb
ruby -e 'require "date"; puts DateTime.now.cweek'
find . -exec grep $foo {} \; -print
2009-12-30 17:41:44
User: linuxgeek
Functions: find grep

The command will help to print the location of the pattern. Above command will print all the files which contain variable "$foo" along with line containing that pattern.

Specify pattern after "grep"

yt-chanrip() { for i in $(curl -s http://gdata.youtube.com/feeds/api/users/"$1"/uploads | grep -Eo "watch\?v=[^[:space:]\"\'\\]{11}" | uniq); do youtube-dl --title --no-overwrites http://youtube.com/"$i"; done }
ans=$(zenity --title "Choose image:" --file-selection); exiftool -s ${ans} | zenity --width 800 --height 600 --text-info;