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 6
  • 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 1009
  • 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 07:41:55 311
  • 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 08:21:55 378
  • 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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A command to copy mysql tables from a remote host to current host via ssh.
In the example above 3 tables are copied. You can change the number of tables. You should be able to come up with variants of the command by modifying the mysqldump part easily, to copy some part of remote mysql DB.

Run a command when a file is changed

Show established network connections

sort lines by length
making it "sound" more "natural" language like -- additionally sorting the longest words alphabetically: this approach is using: * to get at all lines of input * post-"for" structure * short-circuit-or in sort: if the lengths are the same, then sort alphabetically otherwise don't even evaluate the right hand side of the or * -C sets all input and ouput channels to utf8

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)
Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.

Kill all processes that listen to ports begin with 50 (50, 50x, 50xxx,...)
Run netstat as root (via sudo) to get the ID of the process listening on the desired socket. Use awk to 1) match the entry that is the listening socket, 2) matching the exact port (bounded by leading colon and end of column), 3) remove the trailing slash and process name from the last column, and finally 4) use the system(…) command to call kill to terminate the process. Two direct commands, netstat & awk, and one forked call to kill. This does kill the specific port instead of any port that starts with 50. I consider this to be safer.

Use md5sum to check your music and movie files. Also use diff.
This is a beginning script. You can create a file with > filename. You can also use diff to compare output run at different times to verify no change in your files. I apologize in advance if this is too simple. For some it should be a start.

Quick syntax highlighting with multiple output formats
You can specify various output formats, theme styles, etc. $ python -m pygments -o source.png source.py $ python -m pygments -o source.rtf source.py Check available output formats, styles, etc.: $ python -m pygments -L Find pygments module here: http://pygments.org/

Make redirects to localhost via /etc/hosts more interesting
Normally when a site is blocked through /etc/hosts, traffic is just being redirected to a non-existent server that isn't going to respond. This helps get your point across a little more clearly than a browser timeout. Of course you could use any number of codes: http://en.wikipedia.org/wiki/List_of_HTTP_status_codes Obviously, this command can be added to init-rc.d, and more sophisticated responses can be given. Seems noteworthy to mention that the information sent from the browser can be parsed using the bash READ builtin (such as 'while read -t 1 statement; do parsing'), and the connection stays open until the script exits. Take care that you must use EXEC:'bash -c foo.sh', as 'execvp' (socat's method for executing scripts) invokes 'sh', not 'bash'.

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