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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 using read from sorted by
Terminal - Commands using read - 290 results
lynx --dump http://www.seeon.tv/channels| grep "/channels"|awk '{print $2}'|sort -u|while read links; do lynx --dump "$links"|awk '/view/ {print $2}'|sort -u; done
2011-04-01 05:58:20
User: Bonster
Functions: awk grep read sort

This shows a list of channels from seeon.tv website to watch shows and movies

df -h | grep -v ^none | ( read header ; echo "$header" ; sort -rn -k 5)
2011-03-16 14:25:45
User: purpleturtle
Functions: df echo grep read sort
Tags: sort headers df

Show disk space info, grepping out the uninteresting ones beginning with ^none while we're at it.

The main point of this submission is the way it maintains the header row with the command grouping, by removing it from the pipeline before it gets fed into the sort command. (I'm surprised sort doesn't have an option to skip a header row, actually..)

It took me a while to work out how to do this, I thought of it as I was drifting off to sleep last night!

echo "Simplied Chinese:"; while read -r line; do echo "Traditional Chinese:"; echo $line | iconv -f utf8 -t gb2312 | iconv -f gb2312 -t big5 | iconv -f big5 -t utf8; done
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// .*/} $file; fi; done; done
function ds { echo -n "search : "; read ST; EST=`php -r "echo rawurlencode('$ST');"`; B64=`echo -n $ST| openssl enc -base64`; curl -s "http://www.commandlinefu.com/commands/matching/$EST/$B64/plaintext" | less -p "$ST"; } ; bind '"\C-k"':"\"ds\C-m\""
2011-02-20 23:46:16
User: cparker
Functions: echo less read
Tags: bash less curl PHP

This is a simple bash function and a key binding that uses commandlinefu's simple and easy search API. It prompts for a search term, then it uses curl to search commandline fu, and highlights the search results with less.

files -type f | xargs -n100 | while read l; do mkdir $((++f)); cp $l $f; done
2011-02-15 23:15:16
User: flatcap
Functions: cp mkdir read xargs

Take a folder full of files and split it into smaller folders containing a maximum number of files. In this case, 100 files per directory.

find creates the list of files

xargs breaks up the list into groups of 100

for each group, create a directory and copy in the files

Note: This command won't work if there is whitespace in the filenames (but then again, neither do the alternative commands :-)

$ right(){ l="$(cat -)"; s=$(echo -e "$l"| wc -L); echo "$l" | while read l;do j=$(((s-${#l})));echo "$(while ((j-->0)); do printf " ";done;)$l";done;}; ls --color=none / | right
center(){ l="$(cat -)"; s=$(echo -e "$l"| wc -L); echo "$l" | while read l;do j=$(((s-${#l})/2));echo "$(while ((--j>0)); do printf " ";done;)$l";done;}; ls --color=none / | center
2011-02-14 16:50:35
User: glaudiston
Functions: echo ls read wc

Center the output text in max line length of buffered output pipe;

while [ 1 ]; do clear; echo 'YOUR TEXT HERE' | figlet -f banner -t | while IFS="\n" read l; do echo "$l"; sleep 0.01; done; done
2011-02-13 18:52:39
User: lkjoel
Functions: banner echo read sleep

Change YOUR TEXT HERE to the text you want.

On figlet -f banner, you can change it to any figlet font you have installed.

One variant for Star Wars fans could be this:

while [ 1 ]; do clear; echo 'Star Wars' | figlet -f starwars -t | while IFS="\n" read l; do echo "$l"; sleep 0.01; done; done

NOTICE: You need to install figlet.

On Ubuntu, this command is:

sudo apt-get install figlet

On Debian, this command is:

aptitude install figlet
find files/ -type f | while read line; do if [ $((i++%100)) -eq 0 ]; then mkdir $((++folder)); fi; cp $line $folder/; done
exec 3<&0; ls -1N | while read a; do echo "Rename file: $a"; read -e -i "$a" -p "To: " b <&3 ; [ "$a" == "$b" ] || mv -vi "$a" "$b"; done
IFS=$'\n'; i=1; ls -lt *mp3 | cut -d ":" -f2 | cut -d " " -f2- | while read f; do mv "$f" $(echo "$i"."$f"); ((i++)); done
2011-01-22 00:21:12
User: m1cawber
Functions: cut echo ls mv read

i use this after ripping internet radio streams to number the files as they originally played (even though streamripper can do this with -q).

to number other types of files, or all files, just change the *mp3. to rename directories only you could use

... ls -lt | grep ^d | cut -d ":" -f2 | cut -d " " -f2- | while read ...

echo -en "$USER@$HOSTNAME:${PWD##*/}> ";while read x;do echo $x>>/tmp/log.txt;echo $x|$0 2>&1;echo -en "$USER@$HOSTNAME:${PWD##*/}> ";done
bargs { while read i; do "$@" "$i"; done }
exipick -zi | while read x ; do exim -dM "$x"; sleep 1;done
2011-01-04 20:17:30
User: alustenberg
Functions: read sleep
Tags: exim

can also be invoked as 'exipick -zi | exim -dM' if you do not need/want the delay between flushes.

grep -i "$*" /usr/lib/perl5/Unicode/CharName.pm | while read a b; do /usr/bin/printf "\u$a\tU+%s\t%s\n" "$b"; done
2011-01-04 11:30:16
User: ioggstream
Functions: grep read

No need for further filedes or substitution for splitting. Simply use read a b

$ find . -iname *.mp3 | while read line ; do ln -s "$line" $(echo -e "$line" | openssl md5).mp3 ; done ; mpg123 *.mp3
egrep -i "^[0-9a-f]{4,} .*$*" $(locate CharName.pm) | while read h d; do /usr/bin/printf "\U$(printf "%08x" 0x$h)\tU+%s\t%s\n" $h "$d"; done
2010-12-31 16:47:59
User: hackerb9
Functions: egrep locate read

[Update! Thanks to a tip from ioggstream, I've fixed both of the bugs mentioned below.]

You, yes, 𝙔𝙊𝙐, can be the terror of the Internet! Why use normal, boring bullet points in your text, when you could use a ROTATED HEAVY BLACK HEART BULLET (❥)!? (Which would also be an awesome band name, by the way).

This script makes it easy to find unusual characters from the command line. You can then cut and paste them or, if you're using a GTK application, type Control+Shift+U followed by the code point number (e.g., 2765) and then a SPACE.

USAGE: Put this script in a file (I called mine "ugrep") and make it executable. Run it from the command line like so,

ugrep heart

The output will look like this,












You can, of course, use regular expressions. For example, if you are looking for the "pi" symbol, you could do this:

ugrep '\bpi\b'

REQUIREMENTS: Although this is written in Bash, it assumes you have Perl installed because it greps through the Perl Unicode character name module (/usr/lib/perl5/Unicode/CharName.pm). Note that it would not have made more sense to write this in Perl, since the CharName.pm module doesn't actually include a subroutine for looking up a character based on the description. (Weird.)

BUGS: In order to fit this script in the commandlinefu limits, a couple bugs were added. ① Astral characters beyond the BMP (basic multilingual plane) are not displayed correctly, but see below. ② Perl code from the perl module being grepped is sometimes extraneously matched.

MISFEATURES: Bash's printf cannot, given a Unicode codepoint, print the resulting character to the terminal. GNU's coreutils printf (usually "/usr/bin/printf") can do so, but it is brokenly pedantic about how many hexadecimal digits follow the escape sequence and will actually die with an error if you give the wrong number. This is especially annoying since Unicode code points are usually variable length with implied leading zeros. The CharNames.pm file represents BMP characters as 4 hexits, but astral characters as 5. In the actual version of this script that I use, I've kludged around this misfeature by zero-padding to 8 hexits like so,

/usr/bin/printf "\U$(printf "%08x" 0x$hex)"

TIP 1: The author recommends "xsel" for command line cut-and-paste. For example,

ugrep biohazard | xsel

TIP 2: In Emacs, instead of running this command in a subshell, you can type Unicode code points directly by pressing Control-Q first, but you'll likely want to change the default input from octal to hexadecimal. (setq read-quoted-char-radix 16).

TIP 3: Of course, if you're using X, and you want to type one of the more common unusual characters, it's easiest of all to do it with your Compose (aka Multi) key. For example, hitting [Compose] <3 types ♥.

mycommand 2> >(while read line; do echo -e "\e[01;31m$line\e[0m"; done)
2010-12-30 21:42:42
User: confiq
Functions: echo read
Tags: color stderr

in case you run some command in CLI and would like to take read strerr little bit better, you can use the following command. It's also possible to grep it if necessary....

wget -qO - http://ngrams.googlelabs.com/datasets | grep -E href='(.+\.zip)' | sed -r "s/.*href='(.+\.zip)'.*/\1/" | uniq | while read line; do `wget $line`; done
alias -g R=' &; jobs | tail -1 | read A0 A1 A2 cmd; echo "running $cmd"; fg "$cmd"; zenity --info --text "$cmd done"; unset A0 A1 A2 cmd'
2010-12-13 17:44:36
User: pipeliner
Functions: alias echo fg jobs read tail unset

make, find and a lot of other programs can take a lot of time. And can do not. Supppose you write a long, complicated command and wonder if it will be done in 3 seconds or 20 minutes. Just add "R" (without quotes) suffix to it and you can do other things: zsh will inform you when you can see the results.

You can replace zenity with other X Window dialogs program.

read -a ARR <<<'world domination now!'; echo ${ARR[2]};
read -a A<<<".*.**..*....*** 8 9 5 10 6 0 2 11 7 4";for C in `date +"%H%M"|fold -w1`;do echo "${A:${A[C+1]}:4}";done
2010-12-02 22:04:49
User: __
Functions: echo fold read

Like 7171, but fixed typo, uses fewer variables, and even more cryptic!

functions(){ read -p "File name> "; sort -d $REPLY | grep "(){" | sed -e 's/(){//g' | less; }
2010-12-01 18:49:48
User: LinuxMan
Functions: grep read sed sort

This command finds all of the functions defined in any shell script you specify including .bashrc

read -a A <<<"8 9 5 10 6 0 3 11 7 4";B='.*.**..*....***';for C in $(date +"%H%M"|fold -w1);do echo "${B:${A[C]}:4}";done