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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 tr from sorted by
Terminal - Commands tagged tr - 70 results
IFS=?" ; for i in * ; do mv -v $i `echo $i|tr ???????????????????\ aaaeeiooAAAEEIOOOcC_` ; done
shuf -n4 /usr/share/dict/words | tr -d '\n'
for i in {21..79};do echo -e "\x$i";done | tr " " "\n" | shuf | tr -d "\n"
ghc -e "mapM_ (\_->Data.ByteString.Char8.putStr (Data.ByteString.Char8.replicate (1024*1024) '\\255')) [1..24]"
2011-04-05 14:28:54
User: MaskRay
Tags: dd tr

I'm both a one-liner fan and a haskell learner

tr '\0' '\377' < /dev/zero|dd count=$((<bytes>/512))
2011-04-05 14:26:02
User: cfy
Functions: dd tr
Tags: dd tr

the speed is about 500MB/s on my machine.

i think it's fast enough to output not too many bytes.

while a C program may output 1GB per sencond on my machine.

if the size is not the power of 512,you may change the bs and count in dd.

find . -depth -print -execdir rename -f 'y/A-Z/a-z/' '{}' \;
2011-03-25 03:10:27
User: rsimpson
Functions: find rename
Tags: bash find mv rename tr

easier way to recursively change files to lowercase using rename instead

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"
The command is too big to fit here. :( Look at the description for the command, in readable form! :)
2011-01-05 02:45:28
User: hunterm
Functions: at command

Yep, now you can finally google from the command line!

Here's a readable version "for your pleasure"(c):

google() { # search the web using google from the commandline # syntax: google google query=$(echo "$*" | sed "s:%:%25:g;s:&:%26:g;s:+:%2b:g;s:;:%3b:g;s: :+:g") data=$(wget -qO - "https://ajax.googleapis.com/ajax/services/search/web?v=1.0&q=$query") title=$(echo "$data" | tr '}' '\n' | sed "s/.*,\"titleNoFormatting//;s/\":\"//;s/\",.*//;s/\\u0026/'/g;s/\\\//g;s/#39\;//g;s/'amp;/\&/g" | head -1) url="$(echo "$data" | tr '}' '\n' | sed 's/.*"url":"//;s/".*//' | head -1)" echo "${title}: ${url} | http://www.google.com/search?q=${query}" }

Enjoy :)

echo "10 i 2 o $(date +"%H%M"|cut -b 1,2,3,4 --output-delimiter=' ') f"|dc|tac|xargs printf "%04d\n"|tr "01" ".*"
2010-11-24 23:49:21
User: unefunge
Functions: echo printf tr xargs

displays current time in "binary clock" format

(loosely) inspired by: http://www.thinkgeek.com/homeoffice/lights/59e0/



.... - 1st hour digit: 0

*..* - 2nd hour digit: 9 (8+1)

.*.. - 1st minutes digit: 4

*..* - 2nd minutes digit: 9 (8+1)

Prompt-command version:

PROMPT_COMMAND='echo "10 i 2 o $(date +"%H%M"|cut -b 1,2,3,4 --output-delimiter=" ") f"|dc|tac|xargs printf "%04d\n"|tr "01" ".*"'

cd /proc&&ps a -opid=|xargs -I+ sh -c '[[ $PPID -ne + ]]&&echo -e "\n[+]"&&tr -s "\000" " "<+/cmdline&&echo&&tr -s "\000\033" "\nE"<+/environ|sort'

Grabs the cmdline used to execute the process, and the environment that the process is being run under. This is much different than the 'env' command, which only lists the environment for the shell. This is very useful (to me at least) to debug various processes on my server. For example, this lets me see the environment that my apache, mysqld, bind, and other server processes have.

Here's a function I use:

aa_ps_all () { ( cd /proc && command ps -A -opid= | xargs -I'{}' sh -c 'test $PPID -ne {}&&test -r {}/cmdline&&echo -e "\n[{}]"&&tr -s "\000" " "<{}/cmdline&&echo&&tr -s "\000\033" "\nE"<{}/environ|sort&&cat {}/limits' ); }

From my .bash_profile at http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html

tr -cs A-Za-z '\n' | sort | uniq -ci
2010-10-20 04:12:58
Functions: sort tr uniq
Tags: sort uniq tr

Gives the same results as the command by putnamhill using nine less characters.

tr A-Z a-z | tr -cs a-z '\n' | sort | uniq -c
wget -qO - http://i18n.counter.li.org/ | grep 'users registered' | sed 's/.*\<font size=7\>//g' | tr '\>' ' ' | sed 's/<br.*//g' | tr ' ' '\0'
date | md5sum
pwgen 30
tr -cd '[:alnum:]' < /dev/urandom | fold -w30 | head -n1
echo "tee can split a pipe in two"|tee >(rev) >(tr ' ' '_')
2010-08-14 20:38:59
User: axelabs
Functions: echo tee tr

Tee can be used to split a pipe into multiple streams for one or more process to work it. You can add more " >()" for even more fun.

ls | while read -r FILE; do mv -v "$FILE" `echo $FILE | tr -d ' '`; done
2010-08-14 14:10:48
User: IgnitionWeb
Functions: ls mv read tr
Tags: space echo while tr

all files in the directory get moved, in doing so the new name of the file is the original name with out spaces (using translate command)

netstat -rn | grep UG | tr -s " " | cut -d" " -f2
jot -b '#' -s '' $COLUMNS
2010-04-13 22:03:39
User: dennisw
Tags: tr tput printf

For BSD-based systems, including OS X, that don't have seq.

This version provides a default using tput in case $COLUMNS is not set:

jot -b '#' -s '' ${COLUMNS:-$(tput cols)}
printf -v row "%${COLUMNS}s"; echo ${row// /#}
2010-04-13 21:56:46
User: dennisw
Functions: echo printf
Tags: tr tput printf

Pure Bash

This will print a row of characters the width of the screen without using any external executables. In some cases, COLUMNS may not be set. Here is an alternative that uses tput to generate a default if that's the case. And it still avoids using tr.

printf -v row "%${COLUMNS:-$(tput cols)}s"; echo ${row// /#}

The only disadvantage to either one is that they create a variable.

printf "%`tput cols`s"|tr ' ' '#'
seq -s'#' 0 $(tput cols) | tr -d '[:digit:]'
2010-04-01 09:06:44
User: jgc
Functions: seq tput tr
Tags: seq tr tput

Print a row of characters across the terminal. Uses tput to establish the current terminal width, and generates a line of characters just long enough to cross it. In the example '#' is used.

It's possible to use a repeating sequence by dividing the columns by the number of characters in the sequence like this:

seq -s'~-' 0 $(( $(tput cols) /2 )) | tr -d '[:digit:]'


seq -s'-~?' 0 $(( $(tput cols) /3 )) | tr -d '[:digit:]'

You will lose chararacters at the end if the length isn't cleanly divisible.

find . -type d -name '*[A-Z]*' -execdir bash -c '! test -f "$(echo "$0" | tr "[:upper:]" "[:lower:]")"' {} \; -execdir bash -c 'mv "$0" "$(echo "$0" | tr "[:upper:]" "[:lower:]")"' {} \;