Commands using tr (352)

  • Even shorter. Stolen from comment posted by eightmillion.


    7
    tr "\n" " " < file
    randy909 · 2010-12-08 16:13:54 5
  • 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 7
  • 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 10

  • 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 13

  • 7
    tr -dc A-Za-z0-9_ < /dev/urandom | head -c 10 | xargs
    nottings · 2012-10-17 14:04:14 10
  • 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. 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 6
  • 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 4

  • 6
    tr A-Z a-z | tr -cs a-z '\n' | sort | uniq -c
    putnamhill · 2010-10-19 22:49:13 8
  • 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 14

  • 6
    tr -s ' ' | cut -d' ' -f2-
    sesom42 · 2015-05-08 12:47:09 10
  • 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 06:39:37 264

  • 6
    head -4 /etc/passwd | tr : , | sed -e 's/^/| /' -e 's/,/,| /g' -e 's/$/,|/' | column -t -s,
    wuseman1 · 2022-04-22 03:03:15 1343
  • 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
  • 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 8
  • 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 5
  • Get there by going backwards and forgetting the numbers.


    5
    seq -s" " -50 -1 | tr -dc -
    DoNotRememberMe · 2010-03-25 06:00:24 33
  • 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 18
  • 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 15:44:48 183
  • 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 4

  • 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 4
  • 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 17

  • 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 07:41:55 395
  • 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 08:21:55 452
  • 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 19
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a function to find the fastest DNS server
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Print a row of 50 hyphens
This feels more intuitive to me.

Remote backups with tar over ssh
Execute it from the source host, where the source files you wish backup resides. With the minus '-' the tar command deliver the compressed output to the standar output and, trough over the ssh session to the remote host. On the other hand the backup host will be receive the stream and read it from the standar input sending it to the /path/to/backup/backupfile.tar.bz2

Ping all hosts on 192.168.1.0/24
Will report back IP address's of all hosts that are UP.

Get the size of all the directories in current directory

Remove orphaned dependencies on Arch
-Qdt Lists dependencies/packages which are no longer required by any packages -q Output only package name (not the version number) -R Remove package(s) Rest is self-explanatory. I just started out with Arch - so if there is any better/standard method to achieve the same - please suggest.

Write a bootable Linux .iso file directly to a USB-stick
Writes hybrid ISO directly to USB stick; replace /dev/sdb with USB device in question and the ISO image link with the link of your choice

Show errors in the kernel ring buffer
Much more useful then parsing syslog

Replace "space" char with "dot" char in current directory file names

Advanced python tracing
Trace python statement execution and syscalls invoked during that simultaneously


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