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 20:31:26 714
  • 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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Colorize grep output

Slightly better compressed archives
Avoids creating useless directory entries in archive, and sorts files by (roughly) extension, which is likely to group similar files together for better compression. 1%-5% improvement.

check open ports without netstat or lsof

Check ps output to see if file is running, if not start it
This comes in handy if you have daemons/programs that have potential issues and stop/disappear, etc., can be run in cron to ensure that a program remains up no matter what. Be advised though, if a program did core out, you'd likely want to know why (gdb) so use with caution on production machines.

count of down available ips

list files recursively by size

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

grep processes list avoiding the grep itself
Trick to avoid the form: grep process | grep - v grep

See how many more processes are allowed, awesome!
There is a limit to how many processes you can run at the same time for each user, especially with web hosts. If the maximum # of processes for your user is 200, then the following sets OPTIMUM_P to 100. $ OPTIMUM_P=$(( (`ulimit -u` - `find /proc -maxdepth 1 \( -user $USER -o -group $GROUPNAME \) -type d|wc -l`) / 2 )) This is very useful in scripts because this is such a fast low-resource-intensive (compared to ps, who, lsof, etc) way to determine how many processes are currently running for whichever user. The number of currently running processes is subtracted from the high limit setup for the account (see limits.conf, pam, initscript). An easy to understand example- this searches the current directory for shell scripts, and runs up to 100 'file' commands at the same time, greatly speeding up the command. $ find . -type f | xargs -P $OPTIMUM_P -iFNAME file FNAME | sed -n '/shell script text/p' I am using it in my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html especially for the xargs command. Xargs has a -P option that lets you specify how many processes to run at the same time. For instance if you have 1000 urls in a text file and wanted to download all of them fast with curl, you could download 100 at a time (check ps output on a separate [pt]ty for proof) like this: $ cat url-list.txt | xargs -I '{}' -P $OPTIMUM_P curl -O '{}' I like to do things as fast as possible on my servers. I have several types of servers and hosting environments, some with very restrictive jail shells with 20processes limit, some with 200, some with 8000, so for the jailed shells my xargs -P10 would kill my shell or dump core. Using the above I can set the -P value dynamically, so xargs always works, like this. $ cat url-list.txt | xargs -I '{}' -P $OPTIMUM_P curl -O '{}' If you were building a process-killer (very common for cheap hosting) this would also be handy. Note that if you are only allowed 20 or so processes, you should just use -P1 with xargs.

Printing multiple years with Unix cal command
src: http://tinyapps.org/weblog/nix/200907090700_linux_cal_print_multiple_years.html

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