Commands using echo sorted by votes

Commands using echo (1,545)

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quick and easy way of validating a date format of yyyy-mm-dd and returning a boolean

Quick and easy way of validating a date format of yyyy-mm-dd and returning a boolean, the regex can easily be upgraded to handle "in betweens" for mm dd or to validate other types of strings, ex. ip address. Boolean output could easily be piped into a condition for a more complete one-liner.
This is sample output - yours may be different.
-1

echo 2006-10-10 | grep -c '^[0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9]$'

rez0r · 2009-05-11 22:18:43 7
Organize a TV-Series season

It happened to me that I got a season of a tv-show which had all files under the same folder like /home/blah/tv_show/season1/file{1,2,3,4,5,...}.avi But I like to have them like this: /home/blah/tv_show/season1/e{1,2,3,4,5,...}/file{1,2,3,4,5,...}.avi So I can have both the srt and the avi on one folder without cluttering much. This command organizes everything assuming that the filename contains Exx where xx is the number of the episode. You may need to set: IFS=$'\n' if your filenames have spaces.
This is sample output - yours may be different.
-1

season=1; for file in $(ls) ; do dir=$(echo $file | sed 's/.*S0$season$E[0-9]\{2\}$.*/\1/'); mkdir $dir ; mv $file $dir; done

lonecat · 2009-05-27 03:30:58 4
Sort a list of numbers on on line, separated by spaces.

You can replace "sort -nu" with "sort -u" for a word list sorted or "sort -R" for a random-sorted line (edit: corrected) Show Sample Output
This is sample output - yours may be different.
```
$ echo "4 2  3 5  2 52  11" | sed "s/$ \|$$/\n/g" | sort -nu | tr "\n" " "| sed -e "s/^ *//" -e "s/ $//"
2 3 4 5 11 52
```
-1

echo $numbers | sed "s/$ \|$$/\n/g" | sort -nu | tr "\n" " " | sed -e "s/^ *//" -e "s/ $//"

chickenzilla · 2009-06-24 15:12:17 7
dig this
This is sample output - yours may be different.
-1

for dnsREC in $(curl -s http://www.iana.org/assignments/dns-parameters |grep -Eo ^[A-Z\.]+\ |sed 's/TYPE//'); do echo -n "$dnsREC " && dig +short $dnsREC IANA.ORG; done

commandlinefu · 2009-09-01 03:11:18 3
Sort a character string

using awk missed the last char thanks @Josay Show Sample Output
This is sample output - yours may be different.
```
aeeelmoprsst
```
-1

echo sortmeplease | awk '{l=split($1,a,"");asort(a);while(x<=l){printf "%s",a[x];x++ }print "";}'

foob4r · 2009-09-03 10:22:39 4
Capitalize the word with dd
This is sample output - yours may be different.
-1

echo capitalize | { dd bs=1 count=1 conv=ucase 2> /dev/null; cat ;}

twfcc · 2009-09-05 01:49:53 40
search for a file in PATH

search argument in PATH accept grep expressions without args, list all binaries found in PATH Show Sample Output
This is sample output - yours may be different.
```
$ sepath noo
/usr/openwin/bin/ttsnoop
/usr/sbin/snoop
$ sepath ^ps$
/bin/ps
/usr/bin/ps
/usr/ucb/ps
```
-1

function sepath { echo $PATH |tr ":" "\n" |sort -u |while read L ; do cd "$L" 2>/dev/null && find . $ ! -name . -prune $ $ -type f -o -type l $ 2>/dev/null |sed "s@^\./@@" |egrep -i "${*}" |sed "s@^@$L/@" ; done ; }

mobidyc · 2009-09-11 15:03:22 5
search for a file in PATH

Searches in order of the directories of $PATH. Stops after finding the entry; looks for only that fileName. Works in Bourne, Korn, Bash and Z shells. Show Sample Output
This is sample output - yours may be different.
```
/usr/local/bin/fileName
```
-1

for L in `echo :$PATH | tr : '\n'`; do F=${L:-"."}/fileName; if [ -f ${F} -o -h ${F} ]; then echo ${F}; break; fi; done

arcege · 2009-09-11 16:14:36 3
regex to match an ip

Handles everything except octets with 255. Ran through ip generator with variable octet lengths.
This is sample output - yours may be different.
-1

echo 127.0.0.1 | egrep -e '^(([01]?[0-9]{1,2}|2[0-4][0-9]|25[0-4])\.){3}([01]?[0-9]{1,2}|2[0-4][0-9]|25[0-4])$'

arcege · 2009-09-17 17:40:48 3
for loop with leading zero in bash 3

Bash 4 will let you do {00..19} to get leading zeros, but Bash 3 doesn't have that feature. This technique gets you partway there (the sequences need be such that the last digit ranges from zero to nine - you can't use this for something like Bash 4's {03..27}, for example). When this limitation is not a problem, you can avoid some complicated string manipulation for concatenating leading zeros. You can add more digits like this: {0..1}{0..9}{0..9} (ranges from 0 to 99 with up to two leading zeros). To pad with additional zeros: for i in 000{0..1}{0..9}; do echo $i; done or for i in {0..1}{0..9}; do echo "000$i"; done This is useful for creating values to sort or for creating filenames with a fixed format. Note that this will also work: touch {0..1}{0..9} Show Sample Output
This is sample output - yours may be different.
```
00
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
```
-1

for i in {0..1}{0..9}; do echo $i; done

dennisw · 2009-09-18 02:51:12 5
Check if variable is a number
This is sample output - yours may be different.
-1

echo $X | egrep "^[0-9]+$"

sharfah · 2009-10-09 13:59:47 6
Email if you disk is over 90%

Email if you disk is over 90% - www.fir3net.com
This is sample output - yours may be different.
-1

HDD=$(df | awk ' NR>3 (S=$5) (M=$6) { if (S>90) print "Your Systems "M" is """S" Full" } ') ; [[ $HDD ]] && echo "$HDD" | mail -s "Hard-Drives Full" TO@EMAIL.com -- -f FROM@EMAIL.com >/dev/null

felix001 · 2009-10-16 06:52:36 5
Partition a new disk as all one partition tagged as "LInux LVM"

This is a bit hacky, but if you're setting up a bunch of new LUNs, it can save a bunch of time. Also check out sfdisk. The fdisk will fail if, for example, a partition table already exists.
This is sample output - yours may be different.
-1

echo -e "n\np\n1\n\n\nt\n8e\nw" | fdisk /dev/sdX

sud0er · 2009-10-20 16:21:54 5
password generator

make password randomly, default 8 char
This is sample output - yours may be different.
-1

genpass() { local h x y;h=${1:-8};x=( {a..z} {A..Z} {0..9} );y=$(echo ${x[@]} | tr ' ' '\n' | shuf -n$h | xargs);echo -e "${y// /}"; }

twfcc · 2009-10-24 04:05:42 4
Friendly command-not-found message.

This will give you a friendly warning if a command doesn't exists. Show Sample Output
This is sample output - yours may be different.
```
$ aptitypo
...
```
-1

command_not_found_handle() { echo 6661696c626f61742e2e2e0a | xxd -p -r; }

unixmonkey7301 · 2009-12-03 21:33:35 4
Know when you will type :q in your term instead of vi(m), the alias will chewed you out.

For vi(m) users : Add it in your ~/.bashrc Add an "exit" @ the end if you are masochist ;) Show Sample Output
This is sample output - yours may be different.
```
this is NOT vi(m) :/
```
-1

alias :q='tput setaf 1; echo >&2 "this is NOT vi(m) :/"; tput sgr0'

sputnick · 2009-12-08 12:59:44 3
prints line numbers

Yep, is hard, but is a way more flexible using pipe.
This is sample output - yours may be different.
-1

cat infile | while read str; do echo "$((++i)) - $str" ; done;

glaudiston · 2009-12-09 14:05:09 3
prints line numbers

Hi glaudiston, you can save a few chars by leaving out cat and pipe and still enjoy the added flexibility.
This is sample output - yours may be different.
-1

while read str; do echo "$((++i)) - $str"; done < infile

putnamhill · 2009-12-09 15:11:25 3
[Gentoo] Input modules, commented, in your module.autoload file

Whenever you compile a new kernel, there are always new modules. The best way to make sure you have the correct modules loaded when you boot is to add all your modules in the modules.autoload file (they will be commented) and uncomment all those modules you need. Also a good way to keep track of the available modules in your system. For other distros you may have to change the name of the file to /etc/modprobe.conf Show Sample Output
This is sample output - yours may be different.
```
# /etc/modules.autoload.d/kernel-2.6:  kernel modules to load when system boots.
#
# Note that this file is for 2.6 kernels.
#
# Add the names of modules that you'd like to load when the system
# starts into this file, one per line.  Comments begin with # and
# are ignored.  Read man modules.autoload for additional details.

# For example:
# aic7xxx
# mixer-oss.ko
# pcm-oss.ko
# seq-device.ko
# seq-oss.ko
# snd-seq.ko
```
-1

find /lib/modules/`uname -r`/ -type f -iname '*.o' -or -iname '*.ko' |grep -i -o '[a-z0-9]*[-|_]*[0-9a-z]*\.ko$' |xargs -I {} echo '# {}' >>/etc/modules.autoload.d/kernel-2.6

paragao · 2010-01-13 02:12:08 4
displays a reminder message at the specified time
This is sample output - yours may be different.
-1

echo "DISPLAY=$DISPLAY xmessage convert db to innodb" | at 00:00

op4 · 2010-02-04 04:02:35 4
Send web page by e-mail

This will send the web page at $u to recipient@example.com . To send the web page to oneself, recipient@example.com can be replaced by $(whoami) or $USER. The "charset" is UTF-8 here, but any alternative charset of your choice would work. `wget -O - -o /dev/null $u` may be considered instead of `curl $u` . On some systems the complete path to sendmail may be necessary, for instance /sys/pkg/libexec/sendmail/sendmail for some NetBSD.
This is sample output - yours may be different.
-1

{ u="http://twitter.com/commandlinefu"; echo "Subject: $u"; echo "Mime-Version: 1.0"; echo -e "Content-Type: text/html; charset=utf-8\n\n"; curl $u ; } | sendmail $USER

pascalvaucheret · 2010-02-24 04:18:30 5
x bottles of beer on the wall graph

Will create a graph of the results for "x bottles of beer on the wall". Requires Gnuplot. Inspired by an xkcd comic: http://xkcd.com/715/ For sample output see: http://tr.im/xbottlesofbeer Show Sample Output
This is sample output - yours may be different.
```
See http://tr.im/xbottlesofbeer
```
-1

(echo "plot '-' with lines"; for x in $(seq 1 100); do curl -s "http://ajax.googleapis.com/ajax/services/search/web?v=1.0&q=$(echo $x bottles of beer on the wall|sed 's/ /%20/g')"|sed 's/.*"estimatedResultCount":"$[^"]*$".*/\1\n/';done)|gnuplot -persist

matthewbauer · 2010-03-17 21:04:36 4
Split a file into equal size chunks and archive to (e)mail account.

This is just a little snippit to split a large file into smaller chunks (4mb in this example) and then send the chunks off to (e)mail for archival using mutt. I usually encrypt the file before splitting it using openssl: openssl des3 -salt -k <password> -in file.tgz -out file.tgz.des3 To restore, simply save attachments and rejoin them using: cat file.tgz.* > output_name.tgz and if encrypted, decrypt using: openssl des3 -d -salt -k <password> -in file.tgz.des3 -out file.tgz edit: (changed "g" to "e" for political correctness)
This is sample output - yours may be different.
-1

split -b4m file.tgz file.tgz. ; for i in file.tgz.*; do SUBJ="Backup Archive"; MSG="Archive File Attached"; echo $MSG | mutt -a $i -s $SUBJ YourEmail@(E)mail.com

tboulay · 2010-03-20 16:49:19 8
Leap year calculation
This is sample output - yours may be different.
-1

year=2010; math=`echo "$year%4" | bc`; [ ! -z $year ] && [ $math -eq 0 ] && echo "$year is leap year!" || echo "$year isn't leap year";

mvrilo · 2010-03-30 15:33:00 4
Bash function to see if the day ends in

The shell has perfectly adequate pattern matching for simple expressions. Show Sample Output
This is sample output - yours may be different.
```
ok
```
-1

function ends_in_y() { case $(date +%A) in *y ) true ;; * ) false ;; esac } ; ends_in_y && echo ok

unixmonkey9199 · 2010-04-06 22:18:52 3
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Advanced python tracing

Trace python statement execution and syscalls invoked during that simultaneously

Start screen in detached mode

Start screen in detached mode, i.e., already running on background. The command is optional, but what is the purpose on start a blank screen process that way? It's useful when invoking from a script (I manage to run many wget downloads in parallel, for example).

Stop long commands wrapping around and over-writing itself in the Bash shell

add the command either in /etc/profile or ~/.bash_profile so that this is available to your shell.

parrallel execution of a command on remote hosts by ssh or rsh or ...

parrallel execution of a command on remote host by ssh or rsh or ... very useful for cluster management (software update)

Displays the attempted user name, ip address, and time of SSH failed logins on Debian machines

A variation of a script I found on this site and then slimmed down to just use awk. It displays all users who have attempted to login to the box and failed using SSH. Pipe it to the sort command to see which usernames have the most failed logins.

Simple addicting bash game.

hold period (or whatever character) and hit enter after a second. You need to make the next line of periods the same length as the previous line... score starts at 0 and increase each time length of line is same.

Alias TAIL for automatic smart output

Run the alias command, then issue $ps aux | tail and resize your terminal window (putty/console/hyperterm/xterm/etc) then issue the same command and you'll understand. $ ${LINES:-`tput lines 2>/dev/null||echo -n 12`} Insructs the shell that if LINES is not set or null to use the output from `tput lines` ( ncurses based terminal access ) to get the number of lines in your terminal. But furthermore, in case that doesn't work either, it will default to using the default of 80. The default for TAIL is to output the last 10 lines, this alias changes the default to output the last x lines instead, where x is the number of lines currently displayed on your terminal - 7. The -7 is there so that the top line displayed is the command you ran that used TAIL, ie the prompt. Depending on whether your PS1 and/or PROMPT_COMMAND output more than 1 line (mine is 3) you will want to increase from -2. So with my prompt being the following, I need -7, or - 5 if I only want to display the commandline at the top. ( http://www.askapache.com/linux/bash-power-prompt.html ) 275MB/748MB [7995:7993 - 0:186] 06:26:49 Thu Apr 08 [askapache@n1-backbone5:/dev/pts/0 +1] ~ $ In most shells the LINES variable is created automatically at login and updated when the terminal is resized (28 linux, 23/20 others for SIGWINCH) to contain the number of vertical lines that can fit in your terminal window. Because the alias doesn't hard-code the current LINES but relys on the $LINES variable, this is a dynamic alias that will always work on a tty device.

a fast way to repeat output a byte

I'm both a one-liner fan and a haskell learner

Sort processes by CPU Usage

GREP a PDF file.

PDF files are simultaneously wonderful and heinous. They are wonderful in being ubiquitous and mostly being cross platform. They are heinous in being very difficult to work with from the command line, search, grep, use only the text inside the PDF, or use outside of proprietary products. xpdf is a wonderful set of PDF tools. It is on many linux distros and can be installed on OS X. While primarily an open PDF viewer for X, xpdf has the tool "pdftotext" that can extract formated or unformatted text from inside a PDF that has text. This text stream can then be further processed by grep or other tool. The '-' after the file name directs output to stdout rather than to a text file the same name as the PDF. Make sure you use version 3.02 of pdftotext or later; earlier versions clipped lines. The lines extracted from a PDF without the "-layout" option are very long. More paragraphs. Use just to test that a pattern exists in the file. With "-layout" the output resembles the lines, but it is not perfect. xpdf is available open source at http://www.foolabs.com/xpdf/

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Commands using echo (1,545)

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