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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.




Commands tagged Linux from sorted by
Terminal - Commands tagged Linux - 224 results
human_filesize() { awk -v sum="$1" ' BEGIN {hum[1024^3]="Gb"; hum[1024^2]="Mb"; hum[1024]="Kb"; for (x=1024^3; x>=1024; x/=1024) { if (sum>=x) { printf "%.2f %s\n",sum/x,hum[x]; break; } } if (sum<1024) print "1kb"; } '}
2011-12-02 18:21:20
User: ArtBIT
Functions: awk printf

Converts a number of bytes provided as input, to a human readable number.

watch -tn1 'figlet -f slant `date +%T` | cowsay -n -f telebears'
2011-11-25 14:35:01
Functions: watch
Tags: Linux

You need to have figlet(for font) and cowsay installed.

Just copy n paste this command and you can see.....

figlet -f $(ls /usr/share/figlet/fonts/*.flf | shuf -n1) namakukingkong | cowsay -n -f $(ls /usr/share/cows/ | shuf -n1)
2011-11-25 13:54:06
Functions: ls
Tags: Linux

You need to have figlet(for font) and cowsay installed then add it to your .bashrc file.You can see it every time after start a new session.

for x in *.mp3; do y=`echo $x | sed 's/...\(.*\)/\1/' | sed 's/.mp3//ig'`; id3v2 --TIT2 "$y" "$x"; done
2011-11-17 18:57:09
User: robotmachine
Functions: sed
Tags: bash Linux mp3 id3

Assumes that the files are named as such: 01-Filename.mp3

If your files are named differently, change the number of periods in the sed 's/...\(.*\)/\1' bit to match the numbers of characters you need to cut off the front of the file.

Note: This only writes the titles.

x="1" && z="`ls -l * | wc -l`"; for y in *.mp3; do `id3v2 --TRCK "$x/$z" "$y"`; x=$[$x+1]; done
2011-11-17 18:52:59
User: robotmachine
Tags: Linux mp3 id3

Assumes that the files are named in numerical order (ie. 01 Filename.mp3). It will set the track number as tracknumber/totaltracks (ie. 1/14). This will write both ID3v1 and ID3v2 tags.

Note: This only writes the track numbers.

for line in `cat $file`; do firefox -new-tab "$line" & 2>/dev/null; sleep 1; done
2011-11-12 13:47:24
User: hamsolo474
Functions: sleep

this will open a new tab in firefox for every line in a file

the sleep is removable but i found that if you have a large list of urls 50+, and no sleep, it will try to open all the urls at once and this will cause them all to load a lot slower, also depending on the ram of your system sleep gives you a chance to close the tabs before they overload your ram, removing & >2/dev/null will yield unpredictable results.

for D in `mount -lt cifs | sed 's/.*on \(\/.\+\) type.*/\1/'`; do echo -n "UNMOUNTING $D..."; sudo umount $D; echo " [DONE]"; done;
2011-10-19 18:14:19
User: crazedsanity
Functions: echo sed sudo umount

Unmounts all CIFS-based network drives. Very nice for shutting down network mounts on a Linux laptop just prior to going to sleep.

curl -u username --silent "https://mail.google.com/mail/feed/atom" | awk 'BEGIN{FS="\n";RS="(</entry>\n)?<entry>"}NR!=1{print "\033[1;31m"$9"\033[0;32m ("$10")\033[0m:\t\033[1;33m"$2"\033[0m"}' | sed -e 's,<[^>]*>,,g' | column -t -s $'\t'
2011-10-15 23:15:52
User: frntn
Functions: awk column sed

Just an alternative with more advanced formating for readability purpose. It now uses colors (too much for me but it's a kind of proof-of-concept), and adjust columns.

sudo dpkg -i `ls -tr *.deb | tail -n4`
2011-10-09 14:20:11
User: _john
Functions: sudo tail

after kernel build with make deb-pkg, I like to install the 4 newest packages that exist in the directory. Beware: might be fewer for you....

apt-get remove $(dpkg -l | awk "/^ii linux-(image|headers)/ && ! /`uname -r`/ {print \$2}")
2011-10-09 13:58:47
User: _john
Functions: apt awk

since awk was already there one can use it instead of the 2 greps. might not be faster, but fast enough

sed 's/.$//' Win-file.txt
tr -d "\r" < dos.txt > linux.txt
while true ; do nc -l 80 < index.html ; done
2011-08-31 15:17:33
User: ztank1013
Functions: true

Very simple web server listening on port 80 will serve index.html file or whatever file you like pointing your browser at http://your-IP-address/index.html for example.

If your web server is down for maintenance and you'd like to inform your visitors about it, quickly and easily, you just have to put into the index.html file the right HTML code and you are done! Of course you need to be root to run the command using port 80.

find /var/spool/mqueue -type f -mtime +7 | perl -lne unlink
2011-08-19 15:22:02
User: mengesb
Functions: find perl

Find all files in /var/spool/mqueue older than 7 days, pass to perl to efficiently delete them (faster than xargs or -exec when you've got millions or hundreds of thousands to delete). Naturally the type, directory, and file age vars can be adjusted to meet your specific needs.

ln -nsf <TARGET> <LINK>
2011-07-14 14:07:06
User: rdc
Functions: ln
Tags: Linux symlinks

Instead of deleting an existing symlink and then re-creating it pointing at the new location, it is possible to perform the same action with this one command.

Interesting discussion on whether this is possible to do atomically here: http://answers.google.com/answers/threadview?id=526119

find /myfs -size +209715200c -exec du -m {} \; |sort -nr |head -10
2011-07-07 21:12:46
User: arlequin
Functions: du find head sort

Specify the size in bytes using the 'c' option for the -size flag. The + sign reads as "bigger than". Then execute du on the list; sort in reverse mode and show the first 10 occurrences.

ykpersonalize -1 -ostatic-ticket -ostrong-pw1 -ostrong-pw2
2011-05-13 04:00:52

By default, slot 1 is used for OTP purposes and validates against the Yubikey servers. Running the command above will replace that. If you have a Yubikey 2 or above, you can change -1 to -2 and program the second slot with a strong static key.

ip addr show eth0 | grep ether | awk '{print $2}'
2011-05-01 19:54:46
User: ryanc
Functions: awk grep
Tags: Network Linux

Linux specific, requires iproute2 (but most distros have that by default now)

chage -d 0 -m 0 -M 60 [user]
2011-04-28 02:19:59
User: mack
Functions: chage

This command is Linux compatible.

It will prompt the user for a new password at next logon

sudo aptitude remove -P $(dpkg -l|awk '/^ii linux-image-2/{print $2}'|sed 's/linux-image-//'|awk -v v=`uname -r` 'v>$0'|sed 's/-generic//'|awk '{printf("linux-headers-%s\nlinux-headers-%s-generic\nlinux-image-%s-generic\n",$0,$0,$0)}')
2011-04-25 05:19:57
User: Bonster
Functions: awk sed sudo

Same as 7272 but that one was too dangerous

so i added -P to prompt users to continue or cancel

Note the double space: "...^ii␣␣linux-image-2..."

Like 5813, but fixes two bugs: [1]This leaves the meta-packages 'linux-headers-generic' and 'linux-image-generic' alone so that automatic upgrades work correctly in the future. [2]Kernels newer than the currently running one are left alone (this can happen if you didn't reboot after installing a new kernel).

fig2dev -L eps file.fig file.eps
2011-04-25 01:02:25
User: droidery29
Tags: Linux

There is a huge number of supported "languages" to which you can export your .fig figures to. See. 'man fig2dev' (http://linux.die.net/man/1/fig2dev).

php -r 'function a(){$i=10;while($i--)echo str_repeat(" ",rand(1,79))."*".PHP_EOL;}$i=99;while($i--){a();echo str_repeat(" ",34)."Happy New Year 2011".PHP_EOL;a();usleep(200000);}'
2011-04-21 05:08:56
User: galymzhan
Functions: echo
Tags: Linux PHP

Requires installed command line PHP. Also, try at different dimensions of terminal window

function rot13 { if [ -r $1 ]; then cat $1 | tr '[N-ZA-Mn-za-m5-90-4]' '[A-Za-z0-9]'; else echo $* | tr '[N-ZA-Mn-za-m5-90-4]' '[A-Za-z0-9]'; fi }
2011-03-18 09:59:41
User: twjolson
Functions: cat echo tr
Tags: Linux unix tr

Will rot 13 whatever parameter follows 'rot13', whether it is a string or a file. Additionally, it will rot 5 each digit in a number

alias rot13="tr a-zA-Z n-za-mN-ZA-M"
aptitude remove $(dpkg -l|awk '/^ii linux-image-2/{print $2}'|sed 's/linux-image-//'|awk -v v=`uname -r` 'v>$0'|sed 's/-generic//'|awk '{printf("linux-headers-%s\nlinux-headers-%s-generic\nlinux-image-%s-generic\n",$0,$0,$0)}')
2010-12-11 11:38:15
User: __
Functions: awk sed

Note the double space: "...^ii␣␣linux-image-2..."

Like 5813, but fixes two bugs: [1]This leaves the meta-packages 'linux-headers-generic' and 'linux-image-generic' alone so that automatic upgrades work correctly in the future. [2]Kernels newer than the currently running one are left alone (this can happen if you didn't reboot after installing a new kernel).

I'm bummed that this took 228 characters. I'd like to see a simpler version.