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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Search recursively to find a word or phrase in certain file types, such as C code
I have a bash alias for this command line and find it useful for searching C code for error messages. The -H tells grep to print the filename. you can omit the -i to match the case exactly or keep the -i for case-insensitive matching. This find command find all .c and .h files

List your installed Chromium extensions (with url to each page)
Gives you a list for all installed chrome (chromium) extensions with URL to the page of the extension. With this you can easy add a new Bookmark folder called "extensions" add every URL to that folder, so it will be synced and you can access the names from every computer you are logged in. ------------------------------------------------------------------------------------------------------------------ Only tested with chromium, for chrome you maybe have to change the find $PATH.

Convert Squid unixtime logs in human-readable ones
On-the-fly conversion of Unix Time to human-readable in Squid's access.log

Recursively remove all empty directories

Run a command multiple times with different subcommands
it's nice to be able to use the command `ls program.{h,c,cpp}`. This expands to `ls program.h program.c program.cpp`. Note: This is a text expansion, not a shell wildcard type expansion that looks at matching file names to calculate the expansion. More details at http://www.linuxjournal.com/content/bash-brace-expansion I often run multiple commands (like apt-get) one after the other with different subcommands. Just for fun this wraps the whole thing into a single line that uses brace expansion.

list block devices
Shows all block devices in a tree with descruptions of what they are.

sed /pat/!d without using sed (no RE; limited to shell patterns aka globbing)
POSIX requires this "string truncating" functionality. might as well use it, at least for very small tasks where invoking sed and using RE is overkill.

Silently ensures that a FS is mounted on the given mount point (checks if it's OK, otherwise unmount, create dir and mount)
In my example, the mount point is /media/mpdr1 and the FS is /dev/sdd1 /mountpoint-path = /media/mpdr1 filesystem=/dev/sdd1 Why this command ? Well, in fact, with some external devices I used to face some issues : during data transfer from the device to the internal drive, some errors occurred and the device was unmounted and remounted again in a different folder. In such situations, the command mountpoint gave a positive result even if the FS wasn't properly mounted, that's why I added the df part. And if the device is not properly mounted, the command tries to unmount, to create the folder (if it exists already it will also work) and finally mount the FS on the given mount point.

List all databases in Postgres and their (byte/human) sizes, ordering by byte size descending
Get a listing of all of your databases in Postgres and their sizes, ordering by the largest size first. Requires that you give the -d parameter a valid database name that you can connect to.

print a python-script (or any other code) with syntax-highlighting and no loss of indentation

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