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2011-03-12 - Confoo 2011 presentation
Slides are available from the commandlinefu presentation at Confoo 2011: http://presentations.codeinthehole.com/confoo2011/
2011-01-04 - Moderation now required for new commands
To try and put and end to the spamming, new commands require moderation before they will appear on the site.
2010-12-27 - Apologies for not banning the trolls sooner
Have been away from the interwebs over Christmas. Will be more vigilant henceforth.
2010-09-24 - OAuth and pagination problems fixed
Apologies for the delay in getting Twitter's OAuth supported. Annoying pagination gremlin also fixed.




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Terminal - All commands - 11,490 results
bashrc-reload() { builtin unalias -a; builtin unset -f $(builtin declare -F | sed 's/^.*declare[[:blank:]]\+-f[[:blank:]]\+//'); . ~/.bashrc; }
2014-03-02 14:24:18
User: Xk2c
Functions: sed unalias unset

Simply sourcing .bashrc does not function correctly when you edit it and change an alias for a function or the other way round with the *same name*.

I therefor use this function. Prior to re-sourcing .bashrc it unsets all aliases and functions.

pdftk *.pdf cat output merged.pdf
2014-03-02 01:53:37
User: o0110o
Functions: cat

Merge Multiple PDFs In Alphabetical Order

lspci -vv | grep 'Ethernet\|Serial' | awk 'NR == 1{ printf $1 } NR == 2 { print " mac " $7 }' | sed ?e 's/-/:/g' -e 's/:f[ef]:f[ef]//g' -e 's/01:00.0/eth0/g' -e 's/01:00.1/eth1/g' -e 's/01:00.2/eth2/g' -e 's/01:00.3/eth3/g' > /etc/iftab && ifrename
2014-03-01 20:07:18
Functions: awk grep lspci printf sed

for redhat systems works sometimes :S tested on dell poweredge r7+ systems

esxcli network ip interface ipv4 set -i vmk1 -I -N -t static
df -h --total | awk 'NR==1; END{print}'
cat /proc/cpuinfo | grep BogoMIPS | uniq | sed 's/^.*://g' | awk '{print($1 / 4) }'
locate *\\.php|xargs grep --color=always -i -5 "namespace\s.*\W"|less
2014-02-28 13:52:15
Functions: grep locate xargs

Another way to view some code by keyword and basic regular expression

htop -p `pgrep firefox`
git tag rel--`date +%Y-%m-%d--%H-%M-%S` -m "(%) rel: stage"
find . -name "*.txt" | xargs -n 1 perl -pi -w -e "s/text([0-9])/other\$1/g;"
2014-02-28 06:38:38
User: kennethjor
Functions: find perl xargs

Does a search and replace across multiple files with a subgroup replacement.

arecord -q -f cd -d 1 recvol.wav;sox recvol.wav -n stat 2>&1|grep RMS|grep amplitude|cut -d"." -f2|cut -c 1-2>recvol;echo $((`cat recvol`+1))>recvol;rec -t wav - silence 1 0.1 `cat recvol` -1 1.0 `cat recvol`%|lame -s 44.1 -a -v - >record.mp3
2014-02-27 23:23:55
User: geaplanet
Functions: arecord cd cut echo grep stat

It find out the mic recording level at the moment of run the command and if a noise level is higher it starts to record an mp3 file. The resulting file will have only the sounds not the silences.

sudo update-grub
2014-02-27 19:50:25
User: Anshik
Functions: sudo

sudo gedit /etc/default/grub

This would open the Grub configuration file. In this file we have to edit the line




for i in $(find . -regex '.*\/C.*\.cpp'); do svn mv `perl -e 'my $s=$ARGV[0]; $s=~m/(.*\/)C(.*)/; print "$s $1$2"' "$i"`; done
eval $(history | cut -c 8- | grep "adb connect [0-9]" | tail -1)
2014-02-27 14:44:27
User: CanOrhan
Functions: cut eval grep tail

Connects to the last adb connection in history.

pacman -Qdt -q | xargs pacman --noconfirm -R
2014-02-27 05:17:57
User: b_t
Functions: xargs

-Qdt Lists dependencies/packages which are no longer required by any packages

-q Output only package name (not the version number)

-R Remove package(s)

Rest is self-explanatory.

I just started out with Arch - so if there is any better/standard method to achieve the same - please suggest.

convert http://imgs.xkcd.com/comics/now.png -negate /tmp/now.png ; DISPLAY=:0.0 awsetbg -c /tmp/now.png
2014-02-26 15:37:15
User: hybris
Tags: wallpaper xkcd

Get http://xkcd.com/now image, inverts colors (I prefer dark backgrounds) and set it as wallpaper.

You can replace the "convert" part by "wget -q http://imgs.xkcd.com/comics/now.png -O /tmp/now.png" if you prefer light backgrounds.

The DISPLAY variable is here to work as a cron job.

tput rmam
2014-02-26 07:06:37
User: kennyld
Functions: tput
Tags: bash ksh
tput rmam

will disable line wrapping so that long lines are truncated to width of the terminal ($COLUMNS).

tput smam

will re-enable wrapping.

I've always used tput in bash scripts but I guess it works on the command line too.

Doesn't work in all terminals.

See http://www.gnu.org/software/termutils/manual/termutils-2.0/html_chapter/tput_1.html

find . -type d| while read i; do echo $(ls -1 "$i"|wc -m) $(du -s "$i"); done|sort -s -n -k1,1 -k2,2 |awk -F'[ \t]+' '{ idx=$1$2; if (array[idx] == 1) {print} else if (array[idx]) {print array[idx]; print; array[idx]=1} else {array[idx]=$0}}'
2014-02-25 22:50:09
User: knoppix5
Functions: awk du echo find ls read sort wc

Very quick! Based only on the content sizes and the character counts of filenames. If both numbers are equal then two (or more) directories seem to be most likely identical.

if in doubt apply:

diff -rq path_to_dir1 path_to_dir2

AWK function taken from here:


cat cachedump.txt | awk -F : '{print $2":"$1}'
ssh -NL 12345:localhost:631 username@remote_server
catmandu convert JSON to YAML < file.json > file.yaml
2014-02-25 08:27:05

You need to install the Catmandu Perl module via `cpanm Catmandu`

printf -- " -e %s" ${ARRAY[*]}
2014-02-25 03:34:12
User: SEJeff
Functions: printf

[jeff@omniscience container] (master)$ echo docker run $(printf -- " -e %s" ${DOCKER_APP_VARS[*]}) -name 12factorapp mattdm/fedora-small

docker run -e DATABASE_USER=dbuserro, -e DATABASE_PASSWORD=maipass -name 12factorapp mattdm/fedora-small

Note that the printf method by itsself doesn't include a newline (\n), so you'll need to embed it into an echo statement or something that does.

edrv() { N=${1:-edrv}; truncate -s ${2:-256m} $N.img && L=$(losetup -f) && losetup $L $N.img && cryptsetup luksFormat --batch-mode $L && cryptsetup luksOpen $L $N && mkfs.vfat /dev/mapper/$N -n $N; cryptsetup luksClose $N; echo losetup -d $L to unmount; }
2014-02-24 01:38:21
User: snipertyler
Functions: echo losetup

You need to be root to do this. So check the command before running it.

You enter the same password for

Enter LUKS passphrase:

Verify passphrase:

Enter passphrase for /dev/loopn:


You can then copy the .img file to somewhere else.

Loop it it with losetup -f IMAGENAME.img and then mount it with a file manager (eg nemo) or run mount /dev/loopn /media/mountfolder

Acts similar to a mounted flash drive

watch -d -n 2 iptables -nvL
2014-02-23 16:35:03
User: xxdesmus
Functions: iptables watch

This will highlight (with a box over it) any changes since the last refresh.

ps -eo pmem,comm | grep application-name
2014-02-23 13:21:29
User: Darkstar
Functions: grep ps

Displays memory usage for individual instances of an application that spawns multiple instances of itself. This command also works on single process applications.