Commands using tr (349)

  • Join lines

    Even shorter. Stolen from comment posted by eightmillion.


    7
    tr "\n" " " < file
    randy909 · 2010-12-08 16:13:54 4
  • Look for English words in /dev/urandom

    Little faster alternative.


    7
    head -100000 /dev/urandom | strings|tr '[A-Z]' '[a-z]'|sort >temp.txt && wget -q http://www.mavi1.org/web_security/wordlists/webster-dictionary.txt -O-|tr '[A-Z]' '[a-z]'|sort >temp2.txt&&comm -12 temp.txt temp2.txt
    marssi · 2010-12-26 11:04:42 4
  • Terminal Keyboard Shortcut list

    This command will give you a list of available keyboard shortcuts according to stty. Show Sample Output


    7
    echo -e "Terminal shortcut keys\n" && sed -e 's/\^/Ctrl+/g;s/M-/Shift+/g' <(stty -a 2>&1| sed -e 's/;/\n/g' | grep "\^" | tr -d ' ')
    cicatriz · 2011-02-10 17:38:05 5
  • simulated text generator

    Show Sample Output


    7
    tr -dc a-z0-9 </dev/urandom | tr 0-8 \ | tr 9 \\n | sed 's/^[ \t]*//' | fmt -u
    rubenmoran · 2011-02-19 10:29:17 12
  • generate a randome 10 character password


    7
    tr -dc A-Za-z0-9_ < /dev/urandom | head -c 10 | xargs
    nottings · 2012-10-17 14:04:14 9
  • Transforms a file to all uppercase.

    Transforms a file to all uppercase.


    6
    tr '[:lower:]' '[:upper:]' <"$1"
    opexxx · 2009-10-08 11:34:07 3
  • Print a row of characters across the terminal

    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:]' or seq -s'-~?' 0 $(( $(tput cols) /3 )) | tr -d '[:digit:]' You will lose chararacters at the end if the length isn't cleanly divisible. Show Sample Output


    6
    seq -s'#' 0 $(tput cols) | tr -d '[:digit:]'
    jgc · 2010-04-01 09:06:44 5
  • Generate a random left-hand password

    Generates a random 8-character password that can be typed using only the left hand on a QWERTY keyboard. Useful to avoid taking your hand off of the mouse, especially if your username is left-handed. Change the 8 to your length of choice, add or remove characters from the list based on your preferences or kezboard layout, etc.


    6
    </dev/urandom tr -dc '12345!@#$%qwertQWERTasdfgASDFGzxcvbZXCVB' | head -c8; echo ""
    TexasDex · 2010-06-17 19:30:36 3
  • Generate list of words and their frequencies in a text file.


    6
    tr A-Z a-z | tr -cs a-z '\n' | sort | uniq -c
    putnamhill · 2010-10-19 22:49:13 7
  • Create executable, automountable filesystem in a file, with password!

    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. USAGE: SEE SAMPLE OUTPUT 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. Show Sample Output


    6
    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
    rodolfoap · 2013-01-31 01:38:30 13
  • drop first column of output by piping to this


    6
    tr -s ' ' | cut -d' ' -f2-
    sesom42 · 2015-05-08 12:47:09 10
  • draw honeycomb

    tput setaf 1 && tput rev && seq -ws "___|" 81|fold -69|tr "0-9" "_" && tput sgr0 # (brick wall)


    6
    seq -ws "\\__/" 99|fold -69|tr "0-9" " "
    knoppix5 · 2018-11-13 06:39:37 262
  • Print with tabular


    6
    head -4 /etc/passwd | tr : , | sed -e 's/^/| /' -e 's/,/,| /g' -e 's/$/,|/' | column -t -s,
    wuseman1 · 2022-04-22 03:03:15 1003
  • List your largest installed packages.

    Calculates the size on disk for each package installed on the filesystem (or removed but not purged). This is missing the | sort -rn which would put the biggest packges on top. That was purposely left out as the command is slightly on the slow side Also you may need to run this as root as some files can only be checked by du if you can read them ;) Show Sample Output


    5
    dpkg --get-selections | cut -f1 | while read pkg; do dpkg -L $pkg | xargs -I'{}' bash -c 'if [ ! -d "{}" ]; then echo "{}"; fi' | tr '\n' '\000' | du -c --files0-from - | tail -1 | sed "s/total/$pkg/"; done
    pykler · 2009-10-12 14:57:54 5
  • Plot frequency distribution of words from files on a terminal.

    Uses the dumb terminal option in gnuplot to plot a graph of frequencies. In this case, we are looking at a frequency analysis of words in all of the .c files. Show Sample Output


    5
    cat *.c | { printf "se te du\nplot '-' t '' w dots\n"; tr '[[:upper:]]' '[[:lower:]]' | tr -s [[:punct:][:space:]] '\n' | sort | uniq -c | sort -nr | head -n 100 | awk '{print $1}END{print "e"}'; } | gnuplot
    taliver · 2009-11-20 14:53:26 7
  • Another Matrix Style Implementation

    A bit different from some of the other submissions. Has bold and uses all c printable characters. Change the bs=value to speed up and increase the sizes of the bold and non-bold strings.


    5
    echo -ne "\e[32m" ; while true ; do echo -ne "\e[$(($RANDOM % 2 + 1))m" ; tr -c "[:print:]" " " < /dev/urandom | dd count=1 bs=50 2> /dev/null ; done
    psykotron · 2009-12-19 19:05:04 4
  • Print a row of 50 hyphens

    Get there by going backwards and forgetting the numbers.


    5
    seq -s" " -50 -1 | tr -dc -
    DoNotRememberMe · 2010-03-25 06:00:24 32
  • Prepare a commandlinefu command.

    This command will format your alias or function to a single line, trimming duplicate white space and newlines and inserting delimiter semi-colons, so it continues to work on a single line. Show Sample Output


    5
    goclf() { type "$1" | sed '1d' | tr -d "\n" | tr -s '[:space:]'; echo }
    meathive · 2010-06-26 21:44:17 17
  • Get all shellcode on binary file from objdump

    Tired copy paste to get opcode from objdump huh ? Get more @ http://gunslingerc0de.wordpress.com Show Sample Output


    5
    objdump -d ./PROGRAM|grep '[0-9a-f]:'|grep -v 'file'|cut -f2 -d:|cut -f1-6 -d' '|tr -s ' '|tr '\t' ' '|sed 's/ $//g'|sed 's/ /\\x/g'|paste -d '' -s |sed 's/^/"/'|sed 's/$/"/g'
    gunslinger_ · 2010-07-11 15:44:48 112
  • Get a BOFH excuse

    Gets a BOFH excuse from the BOFH excuse server (towel.blinkenlights.nl port 666), and passes it through sed and tr to get rid of telnet connection stuff. Show Sample Output


    5
    telnet towel.blinkenlights.nl 666 | sed "s/=== The BOFH Excuse Server ===//" | tr -d '\n' && echo
    hintss · 2011-03-31 05:50:57 3
  • generate random tone


    5
    paste <(seq 7 | shuf | tr 1-7 A-G) <(seq 7 | shuf) | while read i j; do play -qn synth 1 pluck $i synth 1 pluck mix $2; done
    kev · 2012-04-09 15:22:19 3
  • Convert a script to one-liner

    Opposite: Convert an one-liner to script: foo() { <one-liner> ; } ... typeset -f foo ... unset -f foo


    5
    (sed 's/#.*//g'|sed '/^ *$/d'|tr '\n' ';'|xargs echo) < script.sh
    knoppix5 · 2013-10-26 23:23:51 16
  • Check if your desired password is already available in haveibeenpwnd database. This command uses the API provided by HIBP


    5
    function hibp() { sha1=$(echo -n "$1"|sha1sum|awk '{print toupper($0)}'|tr -d '\n'); curl -s -H $'Referer: https://haveibeenpwned.com/' https://api.pwnedpasswords.com/range/$(echo -n $sha1|cut -c1-5)|grep -i $(echo -n $sha1|cut -c6-40); }
    zmonkey · 2018-08-14 07:41:55 306
  • draw honeycomb

    Fill the entire terminal screen. Is COLUMNS or LINES are undefined run "resize"


    5
    yes "\\__/ " | tr "\n" " " | fold -$((($COLUMNS-3)/6*6+3)) | head -$LINES
    tomhol · 2018-11-23 08:21:55 376
  • Printable random characters

    Reads psuedorandom bytes from /dev/urandom, filtering out non-printable ones. Other character classes can be used, such as [:alpha:], [:digit:] and [:alnum:]. To get a string of 10 lowercase letters: tr -dc '[:lower:]' < /dev/urandom | head -c 10


    4
    tr -dc '[:print:]' < /dev/urandom
    gracenotes · 2009-02-05 21:51:14 18
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cd to (or operate on) a file across parallel directories
This is useful for quickly jumping around branches in a file system, or operating on a parellel file. This is tested in bash. cd to (substitute in PWD, a for b) where PWD is the bash environmental variable for the "working directory"

Replace duplicate files by hardlinks

First pass dvd rip... The set of commands was too long, so I had to separate them into two.
This set of commands will rip a dvd title using a 2 pass mencoder xvid encode. It will provide a great quality rip. It will rip as close to 700MB as possible. (note the bitrate of -700000) Enjoy!

fast access to any of your favorite directory.
example: -------------------------------------------------------------------------------------------- user@ubuntu:~/workspace/SVN/haystak-repos/trunk/internal/src$ addpi -------------------------------------------------------------------------------------------- Now that directory is in the list of fast access directories. You can switch to it anytime like this: -------------------------------------------------------------------------------------------- user@ubuntu:~$ pi internal` user@ubuntu:~/workspace/SVN/haystak-repos/trunk/internal/src$ -------------------------------------------------------------------------------------------- Please note the backquote ( the symbol that shares its key with ~ in the keyboard ) pi will switch you to that directory. To see the list of all fast access directories you have to say "cat ~/.pi"

Insert a line at the top of a text file without sed or awk or bash loops
Just use '-' to use STDIN as an additional input to 'cat'

Restore deleted file from GIT repository
This command will automatically find the latest version of the file that was deleted and restore it to it's previous location. If, of course, your file was kept in a git repository... I found this command on http://stackoverflow.com/a/1113140

Rename HTML files according to their title tag
The above one-liner could be run against all HTML files in a directory. It renames the HTML files based on the text contained in their title tag. This helped me in a situation where I had a directory containing thousands of HTML documents with meaningless filenames.

worse alternative to
worse alternative to ctrl+r: grep the history removing duplicates without sorting (case insensitive search).

get newest jpg picture in a folder
search the newest *.jpg in the directory an make a copy to newest.jpg. Just change the extension to search other files. This is usefull eg. if your webcam saves all pictures in a folder and you like the put the last one on your homepage. This works even in a directory with 10000 pictures.

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