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 20:31:26 708
  • 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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Create a file and manipulate the date

Redirect incoming traffic to SSH, from a port of your choosing
Stuck behind a restrictive firewall at work, but really jonesing to putty home to your linux box for some colossal cave? Goodness knows I was...but the firewall at work blocked all outbound connections except for ports 80 and 443. (Those were wide open for outbound connections.) So now I putty over port 443 and have my linux box redirect it to port 22 (the SSH port) before it routes it internally. So, my specific command would be: $iptables -t nat -A PREROUTING -p tcp --dport 443 -j REDIRECT --to-ports 22 Note that I use -A to append this command to the end of the chain. You could replace that with -I to insert it at the beginning (or at a specific rulenum). My linux box is running slackware, with a kernel from circa 2001. Hopefully the mechanics of iptables haven't changed since then. The command is untested under any other distros or less outdated kernels. Of course, the command should be easy enough to adapt to whatever service on your linux box you're trying to reach by changing the numbers (and possibly changing tcp to udp, or whatever). Between putty and psftp, however, I'm good to go for hours of time-killing.

Force unmount occupied partition
Alternative if "Lazy unmount" (umount -l) doesn't obey. Alternative for NFS: $ umount -f /media/sdb1 Use with caution: forcing to unmount a busy partition can cause data loss!

Send pop-up notifications on Gnome
The title is optional. Options: -t: expire time in milliseconds. -u: urgency (low, normal, critical). -i: icon path. On Debian-based systems you may need to install the 'libnotify-bin' package. Useful to advise when a wget download or a simulation ends. Example: $ wget URL ; notify-send "Done"

Block an IP address from connecting to a server
This appends (-A) a new rule to the INPUT chain, which specifies to drop all packets from a source (-s) IP address.

Play all the music in a folder, on shuffle
Play files in shuffle mode with bash and mpg123. Why bother using big-as-hell stuff like mplayer? This will play all your music files contained in */* (in my case author/song.format) with bash and mplayer showing a nice output.

get all Amazon cloud (amazonws etc) ipv4 subnets

Sorted list of established destination connections
no need grep. its redundant when awk is present.

Adhoc tar backup
Creates a quick backup with tar to a remote host over ssh.

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.

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