Commands using tr (349)

  • Show the ordered header line (with field names) of a CSV file

    This little command (function) shows the CSV header fields (which are field names separated by commas) as an ordered list, clearly showing the fields and their order. Show Sample Output


    0
    function headers { head -1 $* | tr ',' '\12' | pr -t -n ; }
    totoro · 2009-03-25 20:07:47 14
  • log your PC's motherboard and CPU temperature along with the current date

    cat datemp.log 04/01/0902:11:42 Sys Temp: +11.0?C CPU Temp: +35.5?C AUX Temp: +3.0?C Show Sample Output


    0
    date +%m/%d/%y%X|tr -d 'n' >>datemp.log&& sensors|grep +5V|cut -d "(" -f1|tr -d 'n'>> datemp.log && sensors |grep Temp |cut -d "(" -f1|tr -d 'n'>>datemp.log
    f241vc15 · 2009-03-31 18:13:23 4
  • Today's date on a yearly calendar...

    Today's date on a yearly calendar... credits to http://lifehacker.com/250825/cli-fun--todays-date-on-a-yearly-calendar Show Sample Output


    0
    cal -y | tr '\n' '|' | sed "s/^/ /;s/$/ /;s/ $(date +%e) / $(date +%e | sed 's/./#/g') /$(date +%m | sed s/^0//)" | tr '|' '\n'
    luishka · 2009-05-26 20:31:26 709
  • String Capitalization

    Helpful when we want to do mass file renaming(especially mp3s). Show Sample Output


    0
    echo "${STRING}" | tr '[A-Z]' '[a-z]' | awk '{print toupper(substr($0,1,1))substr($0,2);}'
    mohan43u · 2009-06-23 21:11:34 119
  • Migrate gems from one ruby installation to another

    gemInst.sh: #!/bin/bash for i in $@; do if [ "$1" != "$i" ] then echo /newInstall/gem install $1 -v=\"$i\" /newInstall/gem install $1 -v="$i" if [ "$?" != "0" ] then echo -e "\n\nGEM INSTALL ERROR: $1\n\n" echo "$1" > gemInst.err fi fi done


    0
    /originalInstall/gem list | tr -d '(),' | xargs -L 1 sudo ./gemInst.sh
    snakerdlk · 2009-07-09 21:46:06 4
  • Sorting by rows

    Save the script as: sort_file Usage: sort_file < sort_me.csv > out_file.csv This script was originally posted by Admiral Beotch in LinuxQuestions.org on the Linux-Software forum. I modified this script to make it more portable. Show Sample Output


    0
    infile=$1 for i in $(cat $infile) do echo $i | tr "," "\n" | sort -n | tr "\n" "," | sed "s/,$//" echo done
    iframe · 2009-07-12 21:23:37 6
  • Generate Random Passwords


    0
    dd if=/dev/urandom count=200 bs=1 2>/dev/null | tr "\n" " " | sed 's/[^a-zA-Z0-9]//g' | cut -c-16
    amaymon · 2009-08-07 06:32:55 5
  • Picture Renamer

    Renames all the jpg files as their timestamps with ".jpg" extension. Show Sample Output


    0
    ls -1 *.jpg | while read fn; do export pa=`exiv2 "$fn" | grep timestamp | awk '{ print $4 " " $5 ".jpg"}' | tr ":" "-"`; mv "$fn" "$pa"; done
    axanc · 2009-08-10 00:52:22 3
  • Emulate perl 'print "#" x 20, "\n"'


    0
    printf '%*s\n' 20 | tr ' ' '#'
    twfcc · 2009-08-15 22:38:01 3
  • Have a list of directories in a file, ending with newlines and need to run du on it?

    du only accepts lines ending with a NUL, which can be a pain to create. This solves that issue.


    0
    cat filename | tr '\n' '\0' | du -hsc ?files0-from=-
    Diluted · 2009-08-21 18:36:49 4
  • Sort a character string

    another possibility


    0
    echo sortmeplease|sed 's/./&\n/g'|sort|tr -d '\n'
    foob4r · 2009-09-03 10:37:57 3
  • Substitution cipher

    This is just for fun. Show Sample Output


    0
    echo "Decode this"| tr [a-zA-Z] $(echo {a..z} {A..Z}|grep -o .|sort -R|tr -d "\n ")
    dennisw · 2009-09-18 06:38:28 36
  • Find duplicate dir in path


    0
    echo $PATH|tr : '\n'|sort|uniq -d
    haivu · 2009-09-24 17:22:45 3
  • Command to resolve name from Ip address, passing only the last field after seq (C Class for example)

    Show Sample Output


    0
    seq 4|xargs -n1 -i bash -c "echo -n 164.85.216.{} - ; nslookup 164.85.216.{} |grep name"|tr -s ' ' ' '|awk '{print $1" - "$5}'|sed 's/.$//'
    Waldirio · 2009-10-14 19:57:24 3
  • Show the command line of a process that use a specific port (ubuntu)

    A way not so simple but functional for print the command for the process that's listening a specific port. I got the pid from lsof because I think it's more portable but can be used netstat netstat -tlnp Show Sample Output


    0
    port=8888;pid=$(lsof -Pan -i tcp -i udp | grep ":$port"|tr -s " " | cut -d" " -f2); ps -Afe|grep "$pid"|grep --invert-match grep | sed "s/^\([^ ]*[ ]*\)\{7\}\(.*\)$/\2/g"
    glaudiston · 2010-01-11 17:49:22 8
  • Create unique email addresses directly from the US census site*Full command in comments

    ** Replace the ... in URLS with: www.census.gov/genealogy/www/data/1990surnames Couldn't fit in 256 Created on Ubuntu 9.10 but nothing out of the ordinary, should work anywhere with a little tweaking. 5163 is the number of unique first names you get when combine the male and female first name files from. http://www.census.gov/genealogy/www/data/1990surnames/names_files.html Show Sample Output


    0
    paste -d "." <(curl http://.../dist.female.first http://.../dist.male.first | cut -d " " -f 1 | sort -uR) <(curl http://..../dist.all.last | cut -d " " -f 1 | sort -R | head -5163) | tr "[:upper:]" "[:lower:]" | sed 's/$/@test.domain/g'
    connorsy · 2010-01-21 19:52:28 3
  • Define words with google. (busybox version)

    This is a minimalistic version of the ubiquitious Google definition screen scraper. This version was designed not only to run fast, but to work using BusyBox. BusyBox is a collection of basic Unix tools that have been compiled into a single binary to save space on tiny installations of Unix. For example, although my phone doesn't have perl or the GNU utilities, it does have BusyBox's stripped down versions of wget, tr, and sed. It turns out that those tools suffice for many tasks. Known Bugs: This script does not handle HTML entities at all. I don't think there's an easy way to do that within BusyBox, but I'd love to see it if someone could do it. Also, this script can only define a single word, not phrases. (Well, you could if you typed in %20, but that'd be gross.) Lastly, this script does not show the URL where definitions were found. Given the randomness of the Net, that last bit of information is often key. Show Sample Output


    0
    wget -q -U busybox -O- "http://www.google.com/search?ie=UTF8&q=define%3A$1" | tr '<' '\n' | sed -n 's/^li>\(.*\)/\1\n/p'
    hackerb9 · 2010-02-01 13:01:47 9
  • Automagically create a /etc/hosts file based on your DHCP list (only works on Linksys WRT54G router)

    Will create a sample etc host file based on your router's dhcp list. Now I know this won't work on most routers, so please don't downvote it just because it doesn't work for you. Show Sample Output


    0
    curl -s -u $username:$password http://192.168.1.1/DHCPTable.htm | grep '<td>.* </td>' | sed 's|\t<td>\(.*\) </td>\r|\1|' | tr '\n' ';' | sed 's/\([^;]*\);\([^;]*\);/\2\t\1\n/g'
    matthewbauer · 2010-02-16 02:27:11 3
  • Reconstruct a malformed authorizated_keys for ssh

    when someone mail you his ssh public key, and the lines are broken with '\n', you can reconstruct a new file with one key by line with this command. Show Sample Output


    0
    cat authorized_keys_with_broken_lines | sed 's,^ssh,%ssh,' | tr '\n' '\0' | tr '%' '\n' | sed '1d' | sed "/^$/d" > authorized_keys
    pepin · 2010-02-19 08:32:35 3
  • list all instances of a file in your PATH directories (without duplicates) in PATH order

    The wherepath function will search all the directories in your PATH and print a unique list of locations in the order they are first found in the PATH. (PATH often has redundant entries.) It will automatically use your 'ls' alias if you have one or you can hardcode your favorite 'ls' options in the function to get a long listing or color output for example. Alternatives: 'whereis' only searches certain fixed locations. 'which -a' searches all the directories in your path but prints duplicates. 'locate' is great but isn't installed everywhere (and it's often too verbose). Show Sample Output


    0
    function wherepath () { for DIR in `echo $PATH | tr ":" "\n" | awk '!x[$0]++ {print $0}'`; do ls ${DIR}/$1 2>/dev/null; done }
    mscar · 2010-04-02 20:32:36 17
  • Get Unique Hostnames from Apache Config Files

    Get a list of all the unique hostnames from the apache configuration files. Handy to see what sites are running on a server.


    0
    cat /etc/apache2/sites-enabled/* | egrep 'ServerAlias|ServerName' | tr -s " " | sed 's/^[ ]//g' | uniq | cut -d ' ' -f 2 | sed 's/www.//g' | sort | uniq
    chronosMark · 2010-04-08 08:51:17 5
  • Create a log file of Nvidia graphics card temperatures using nvidia-smi


    0
    logfile=/var/log/gputemp.log; timestamp=$( date +%T );temps=$(nvidia-smi -lsa | grep Temperature | awk -F: ' { print $2 } '| cut -c2-4 | tr "\n" " ");echo "${timestamp} ${temps}" >> ${logfile}
    purehate · 2010-05-28 10:14:47 6
  • Generate an over-the-top UUID

    first off, if you just want a random UUID, here's the actual command to use: uuidgen Your chances of finding a duplicate after running this nonstop for a year are about the same as being hit by a meteorite before finishing this sentence The reason for the command I have is that it's more provably unique than the one that uuidgen creates. uuidgen creates a random one by default, or an unencrypted one based on time and network address if you give it the -t option. Mine uses the mac address of the ethernet interface, the process id of the caller, and the system time down to nanosecond resolution, which is provably unique over all computers past, present, and future, subject to collisions in the cryptographic hash used, and the uniqueness of your mac address. Warning: feel free to experiment, but be warned that the stdin of the hash is binary data at that point, which may mess up your terminal if you don't pipe it into something. If it does mess up though, just type reset Show Sample Output


    0
    printf $(( echo "obase=16;$(echo $$$(date +%s%N))"|bc; ip link show|sed -n '/eth/ {N; p}'|grep -o -E '([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}'|head -c 17 )|tr -d [:space:][:punct:] |sed 's/[[:xdigit:]]\{2\}/\\x&/g')|sha1sum|head -c 32; echo
    camocrazed · 2010-07-14 14:04:53 10
  • Which machine have I logged in from?


    0
    TTY=$(tty | cut -c 6-);who | grep "$TTY " | awk '{print $6}' | tr -d '()'
    sharfah · 2010-08-06 13:42:17 6
  • Converts uppercase chars in a string to lowercase

    Another way to do it with slightly fewer characters. It doesn't work on Russian characters; please don't vote down because of that. :p It's very handy for those of us working in ascii :) Show Sample Output


    0
    echo StrinG | tr 'A-Z' 'a-z'
    randy909 · 2010-08-12 15:42:56 3
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Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

how many pages will my text files print on?
This gives a very rough estimate of how many pages your text files will print on. Assumes 60 lines per page, and does not take long lines into account.

Find and display most recent files using find and perl
This pipeline will find, sort and display all files based on mtime. This could be done with find | xargs, but the find | xargs pipeline will not produce correct results if the results of find are greater than xargs command line buffer. If the xargs buffer fills, xargs processes the find results in more than one batch which is not compatible with sorting. Note the "-print0" on find and "-0" switch for perl. This is the equivalent of using xargs. Don't you love perl? Note that this pipeline can be easily modified to any data produced by perl's stat operator. eg, you could sort on size, hard links, creation time, etc. Look at stat and just change the '9' to what you want. Changing the '9' to a '7' for example will sort by file size. A '3' sorts by number of links.... Use head and tail at the end of the pipeline to get oldest files or most recent. Use awk or perl -wnla for further processing. Since there is a tab between the two fields, it is very easy to process.

list files recursively by size

Find Duplicate Files (based on size first, then MD5 hash)
for OS X

Scans for open ports using telnet

Efficient count files in directory (no recursion)
$ time perl -e 'if(opendir D,"."){@a=readdir D;print $#a - 1,"\n"}' 205413 real 0m0.497s user 0m0.220s sys 0m0.268s $ time { ls |wc -l; } 205413 real 0m3.776s user 0m3.340s sys 0m0.424s ********* ** EDIT: turns out this perl liner is mostly masturbation. this is slightly faster: $ find . -maxdepth 1 | wc -l sh-3.2$ time { find . -maxdepth 1|wc -l; } 205414 real 0m0.456s user 0m0.116s sys 0m0.328s ** EDIT: now a slightly faster perl version $ perl -e 'if(opendir D,"."){++$c foreach readdir D}print $c-1,"\n"' sh-3.2$ time perl -e 'if(opendir D,"."){++$c foreach readdir D}print $c-1,"\n"' 205414 real 0m0.415s user 0m0.176s sys 0m0.232s

Remove executable bit from all files in the current directory recursively, excluding other directories
With GNU chmod at least it is that simple.

Check the current price of Bitcoin in USD

Find the most recently changed files (recursively)

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