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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!

Top Tags



Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

Commands using tr from sorted by
Terminal - Commands using tr - 288 results
while true; do (date | tr "\n" ";") && ping -q -c 1 www.google.com|tail -1|cut -d/ -f5 ;sleep 1; done >> uptime.csv
2013-02-06 22:06:09
User: fanchok
Functions: cut date ping sleep tail tr

Used in OS X.

tr "\n" ";"

may be replaced by

echo ";"

with linux versions of date.

I reused

ping -q -c 1 www.google.com|tail -1|cut -d/ -f5

dd if=/dev/zero of=T bs=1024 count=10240;mkfs.ext3 -q T;E=$(echo 'read O;mount -o loop,offset=$O F /mnt;'|base64|tr -d '\n');echo "E=\$(echo $E|base64 -d);eval \$E;exit;">F;cat <(dd if=/dev/zero bs=$(echo 9191-$(stat -c%s F)|bc) count=1) <(cat T;rm T)>>F
2013-01-31 01:38:30
User: rodolfoap

This is just a proof of concept: A FILE WHICH CAN AUTOMOUNT ITSELF through a SIMPLY ENCODED script. It takes advantage of the OFFSET option of mount, and uses it as a password (see that 9191? just change it to something similar, around 9k). It works fine, mounts, gets modified, updated, and can be moved by just copying it.


The file is composed of three parts:

a) The legible script (about 242 bytes)

b) A random text fill to reach the OFFSET size (equals PASSWORD minus 242)

c) The actual filesystem

Logically, (a)+(b) = PASSWORD, that means OFFSET, and mount uses that option.

PLEASE NOTE: THIS IS NOT AN ENCRYPTED FILESYSTEM. To improve it, it can be mounted with a better encryption script and used with encfs or cryptfs. The idea was just to test the concept... with one line :)

It applies the original idea of http://www.commandlinefu.com/commands/view/7382/command-for-john-cons for encrypting the file.

The embedded bash script can be grown, of course, and the offset recalculation goes fine. I have my own version with bash --init-file to startup a bashrc with a well-defined environment, aliases, variables.

ls -l /dev/disk/by-id | egrep ata-.*`hdparm -i /dev/sda | grep SerialNo | sed 's/.*SerialNo=//' | tr -d "\n"`.*sda$ | sed -e 's/.*ata-/ata-/' -e 's|[ ].*||' | tr -d "\n"
2013-01-07 10:20:25
Functions: egrep grep ls sed tr
Tags: Ubuntu

This was tested on Ubuntu 12.04 (Precise) LTS Server. It returns the name of the symlink within /dev/disk/by-id for the physical drive you specify. Change /dev/sda to the one you want, and replace ata- with scsi- or the appropriate type for your drive.

I used this to pre-configure grub-pc during a non-interactive install because I had to tell it which disk to install grub on, and physical disks don't have a UUID such as that blkid provides.

tr -s ' \t' <1.txt >2.txt
2012-12-19 07:36:00
User: knoppix5
Functions: tr

Remove empty lines additionally:

tr -s ' \t\n' <1.txt >2.txt

identical with:

tr -s '[:space:]' <1.txt >2.txt

To "clean perfectly" a text or code file, You can combine this command with

another one:

while read l; do echo -e "$l"; done <1.txt >2.txt

(= remove all leading and trailing spaces or tabs from all lines of a text file)

export DISPLAY=$(tr '\000' '\n' < /proc/`pidof Xorg`/cmdline | egrep '^:[0-9]+')
2012-12-18 07:26:16
User: oernii2
Functions: egrep export tr

Not always does Xorg run on :0. For times like those, this script allows you to find out which it is.

dig @resolver1.opendns.com myip.opendns.com | grep ^myip.opendns.com | tr '\t' : | cut -d: -f5
cd ~/.msf4/loot && cat *mscache* | cut -d '"' -f 2,4 | sed s/\"/\:/g | tr -cd '\11\12\40-\176' | grep -v Username | cut -d : -f 1,2 | awk -F':' '{print $2,$1}' | sed 's/ /:/g' > final.dcc.hash
tr -dc '[:print:]' < <file>
2012-11-22 06:29:26
User: seb1245
Functions: tr
Tags: printing tr

tr has some predefined sets of characters that are more convenient to use than characters codes

cat /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 18 | head -1 | python -c "import sys,crypt; stdin=sys.stdin.readline().rstrip('\n'); print stdin;print crypt.crypt(stdin)"
2012-11-09 00:40:22
User: cnyg
Functions: cat fold head python tr

Generate a 18 character password from character set a-zA-Z0-9 from /dev/urandom, pipe the output to Python which prints the password on standard out and in crypt sha512 form.

tr -d '\r' < <input> > <output>
echo "your string here" | tr '\!-~' 'P-~\!-O'
2012-11-06 12:49:00
User: DevEd
Functions: echo tr

This command will encode a string using the ROT47 cipher.

java -jar app.jar -cp $(echo lib/*.jar | tr ' ' ':')
2012-10-29 12:51:46
User: xymor
Functions: echo tr
Tags: java cli

Lauching an app including jars in an adjacent lib folder to its classpath

tr -dc '[:graph:]' </dev/urandom | head -c30; echo
head -c7 /dev/urandom|base64|tr -d '='
tr -dc A-Za-z0-9_ < /dev/urandom | head -c 10 | xargs
echo $(</dev/urandom tr -dc 1-6 | head -c1)
tr -cd '1-6' < /dev/urandom | head -c 1; echo
2012-09-21 02:16:42
User: atoponce
Functions: head tr

/dev/urandom is cryptographically secure, and indistinguishable from true random, as it gathers data from external sources, influenced by human timing interactions with computers, to fill the entropy pool, and hashes the input with SHA-1. As such, this is a quick way to do a "true random" fair-6 dice roll. Using this method, you could easily create passphrases with Diceware http://diceware.com.

Change the head(1) count to something other than 5 for more or less numbers.

echo $(find <directory> -name '*.<extension>' -exec du -s {} \; | tee $(tty) | cut -f1 | tr '\n' '+') 0 | bc
2012-09-17 22:46:50
User: ysangkok
Functions: cut du echo find tee tr

Also shows files as they are found. Only works from a tty.

tcpdump -ntr NAME_OF_CAPTURED_FILE.pcap 'tcp[13] = 0x02 and dst port 80' | awk '{print $4}' | tr . ' ' | awk '{print $1"."$2"."$3"."$4}' | sort | uniq -c | awk ' {print $2 "\t" $1 }'
lsof -p `pidof pidgin` | awk '{ print $9 }'|egrep `hostname` | grep -o ">[^:]\+:" | tr -d ":>" | while read line; do host $line; done;
pbpaste | tr '\r\n' '\n' | tr '\r' '\n' | pbcopy
2012-07-31 10:50:14
User: adambrenecki
Functions: tr

Copying and pasting from Office documents open in Office:mac can dirty your files with Windows CRLF and (inexplicably) Classic Mac OS LF newlines, which can break some tools. This snippet replaces them with good ol' Unix LF newlines.

export PATH= $(echo $PATH | tr ':' '\n' | awk '!/matching string/' | paste -sd:)
ssh-keygen -l -f [pubkey] | cut -d ' ' -f 2 | tr -ds '\n:' ''
tr -s ' '
2012-06-26 19:34:18
User: ankush108
Functions: tr
Tags: tr

Convert long list of ' ' to a single space. Compress space and other characters.

tr a-z A-Z < file.txt