Hide

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again.

Delete that bloated snippets file you've been using and share your personal repository with the world. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

If you have a new feature suggestion or find a bug, please get in touch via http://commandlinefu.uservoice.com/

Get involved!

You can sign-in using OpenID credentials, or register a traditional username and password.

OpenID

First-time OpenID users will be automatically assigned a username which can be changed after signing in.

Hide

Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for:

» all commands
» commands with 3 up-votes (commandlinefu3)
» commands with 10 up-votes (commandlinefu10)
» commands using egrep

Hide

News

2011-03-12 - Confoo 2011 presentation: Slides are available from the commandlinefu presentation at Confoo 2011: http://presentations.codeinthehole.com/confoo2011/
2011-01-04 - Moderation now required for new commands: To try and put and end to the spamming, new commands require moderation before they will appear on the site.
2010-12-27 - Apologies for not banning the trolls sooner: Have been away from the interwebs over Christmas. Will be more vigilant henceforth.
2010-09-24 - OAuth and pagination problems fixed: Apologies for the delay in getting Twitter's OAuth supported. Annoying pagination gremlin also fixed.

Hide

Functions

Hide

Credits

Site by David Winterbottom (user root).

Commands using egrep

Terminal - Commands using egrep - 169 results

for i in `ndd /dev/ip \? | awk '{ print $1 }' | egrep -v "ip6|status|icmp|igmp|\?"` ; do echo $i `ndd -get /dev/ip $i` ; done | grep -v \?

2010-02-15 12:32:33

User: felix001

Functions: awk echo egrep grep

Up
Down

Show the ndd ip settings of a solaris device

This command is jsut for the main IP settings of ndd. if you need ip6 or icmp edit the text within the egrep inclusion area.

Felix001 - www.Fir3net.com

function svnurl() { svn info $1 | egrep '^URL: (.*)' | sed s/URL\:\ //; }

2010-02-12 15:42:54

User: thebuckst0p

Functions: egrep info sed

Up
Down

Extract URL from SVN working copy

Can be used in a working copy to output the URL (extracted from svn info), or as part of another function, as $(svnurl some/path). Saves a lot of time in my SVN workflow.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

sudo netselect -v -s3 $(curl -s http://dns.comcast.net/dns-ip-addresses2.php | egrep -o '[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+' | sort | uniq)

2010-01-27 00:03:44

User: hackerb9

Functions: egrep sort sudo

Tags: DNS netselect fastest server /etc/resolv.conf Comcast

Up
Down

Find the fastest server to disable comcast's DNS hijacking

Comcast is an ISP in the United States that has started hijacking DNS requests as a "service" for its customers. For example, in Firefox, one used to be able to do a quick "I'm Feeling Lucky" Google search by typing a single word into the URL field, assuming the word is not an existing domain when surrounded by www.*.com. Comcast customers never receive the correct NX (non-existent domain) error from DNS. Instead, they are shown a page full of advertising. There is a way to "opt out" from their service, but that requires having the account password and the MAC address of your modem handy. For me, it was easier just to set static DNS servers. But the problem is, which ones to choose? That's what this command answers. It'll show you the three _non-hijacked_ Comcast DNS servers that are the shortest distance away.

Perhaps you don't have Comcast (lucky you!), but hopefully this command can serve as an example of using netselect to find the fastest server from a list. Note that, although this example doesn't show it, netselect will actually perform the uniq and DNS resolution for you.

Requires: netselect, curl, sort, uniq, grep

nmap -T4 -sP 192.168.2.0/24 && egrep "00:00:00:00:00:00" /proc/net/arp

2010-01-22 20:36:43

User: wincus

Functions: egrep

Up
Down

Find unused IPs on a given subnet

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

nmap -sP <subnet>.* | egrep -o '[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+' > results.txt ; for IP in {1..254} ; do echo "<subnet>.${IP}" ; done >> results.txt ; cat results.txt | sort -n -t . -k 1,1 -k 2,2 -k 3,3 -k 4,4 | uniq -u

2010-01-22 00:26:42

User: bortoelnino

Functions: cat echo egrep sort uniq

Up
Down

Find unused IPs on a given subnet

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

lynx --dump --source http://www.xkcd.com | grep `lynx --dump http://www.xkcd.com | egrep '(png|jpg)'` | grep title | cut -d = -f2,3 | cut -d '"' -f2,4 | sed -e 's/"/|/g' | awk -F"|" ' { system("display " $1);system("echo "$2); } '

2009-12-03 18:53:57

User: solarislackware

Functions: awk cut egrep grep

Tags: bash curl function xkcd comic webcomic

-1

Up
Down

View the newest xkcd comic.

Same thing just a different way to get there. You will need lynx

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

egrep -i "somepattern" `find . -type f -print`

2009-12-02 16:00:46

User: dudleyperkins

Functions: egrep

-2

Up
Down

search for a pattern (regex) in all text files (ignoring binary files) in a directory tree

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

find . -type f | perl -lne 'print if -T;' | xargs egrep "somepattern"

2009-12-01 19:12:03

User: unixmonkey7263

Functions: egrep find perl xargs

-1

Up
Down

search for a pattern (regex) in all text files (ignoring binary files) in a directory tree

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

egrep 'https?://([[:alpha:]]([-[:alnum:]]+[[:alnum:]])*\.)+[[:alpha:]]{2,3}(:\d+)?(/([-\w/_\.]*(\?\S+)?)?)?'

2009-11-28 15:41:42

User: putnamhill

Functions: egrep

Tags: regex url match url matching

Up
Down

Match a URL

For the record: I didn't build this. Just shared what I found that worked. Apologies to the original author!

I decided I should fix the case where http://example.com is not matched for the next time I need this. So I read rfc1035 and formalized the host name regex.

If anyone finds any more holes, please comment.

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

egrep "<link>|<title>" recenttracks.rss | awk 'ORS=NR%2?" ":"\n"' | awk -F "</title>" '{print $2, $1}' | sed -e 's/\<link\>/\<li\>\<a href\=\"/' -e 's/\<\/link\>/\">/' -e 's/\<title\>//' -e 's/$/\<\/a\>\<\/li\>/g' -e '1,1d' -e 's/^[ \t]*//'

2009-11-28 13:19:05

User: HerbT

Functions: awk egrep sed

Up
Down

last.fm rss parser

Quick and kludgy rss parser for the recent tracks rss feed from last.fm. Extracts artist and track link.

2009-11-17 02:13:34

User: mohan43u

Functions: cut egrep lsmod modinfo sed xargs

Tags: xargs lsmod modinfo

Up
Down

Short Information about loaded kernel modules

Run this as root, it will be helpful to quickly get information about the loaded kernel modules.

geoip () { curl -s "http://www.geoiptool.com/?IP=$1" | html2text | egrep --color 'City:|IP Address:|Country:' }

2009-11-15 17:59:23

User: wizel

Functions: egrep

Tags: IP geographical location

Up
Down

Provides external IP, Country and City in a formated manner.

If used without arguments, returns own IP info.

If used with argument, returns info about the parsed argument.

ls -a | egrep "^\.\w"

2009-11-11 18:19:56

User: kulor

Functions: egrep ls

Tags: egrep ls dotfiles

-2

Up
Down

Find all dot files and directories

trying to copy all your dotfiles from one location to another, this may help

egrep -v "^[[:blank:]]*($|#|//|/\*| \*|\*/)" somefile

2009-11-10 18:49:19

User: sdadh01

Functions: egrep

Tags: sed PHP

Up
Down

Show a script or config file without comments

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

find ~/Maildir/ -mindepth 1 -type d | egrep -v '/cur$|/tmp$|/new$' | xargs

2009-11-05 14:11:29

User: ook

Functions: egrep find

Tags: mutt Maildir mailboxes

Up
Down

Build an exhaustive list of maildir folders for mutt

Of course, you can adjust "Maildir" to your config...

tail -F file | egrep --color 'pattern|$'

2009-10-16 04:01:14

User: sklm

Functions: egrep file tail

Tags: color

Up
Down

tail, with specific pattern colored

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

tail -f file | egrep --color=always $\|PATTERN

2009-10-15 13:08:30

User: sitaram

Functions: egrep file tail

Tags: color

-2

Up
Down

tail, with specific pattern colored

but you can't see the colors in that sample output :(

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

2009-10-09 13:59:47

User: sharfah

Functions: echo egrep

-1

Up
Down

Check if variable is a number

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

egrep 'Failed password for invalid' /var/log/secure | awk '{print $13}' | uniq

2009-10-04 18:08:13

User: servermanaged

Functions: awk egrep

Up
Down

Grep auth log and print ip of attackers

Work for me on CentOS, grep and print ip addresses of ssh bruteforce attempts

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])$'

2009-09-17 17:40:48

User: arcege

Functions: echo egrep

Tags: IP grep regex ip address

-1

Up
Down

regex to match an ip

Handles everything except octets with 255. Ran through ip generator with variable octet lengths.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

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 ; }

2009-09-11 15:03:22

User: mobidyc

Functions: cd echo egrep find read sed sort tr

Tags: bash ksh PATH

-1

Up
Down

search for a file in PATH

search argument in PATH

accept grep expressions

without args, list all binaries found in PATH

function catv { egrep -v "^$|^#" ${*} ; }

2009-09-11 14:58:47

User: mobidyc

Functions: egrep

Tags: Text Processing conffiles

Up
Down

Output files without comments or empty lines

better integration.

works on all Unices

works one bash and ksh.

wget -nv http://en.wikipedia.org/wiki/Linux -O- | egrep -o "http://[^[:space:]]*.jpg" | xargs -P 10 -r -n 1 wget -nv

2009-08-31 18:37:33

User: syssyphus

Functions: egrep wget xargs

Up
Down

Parallel file downloading with wget

xargs can be used in this manner to download multiple files at a time, and xargs will in this case run 10 processes at a time and initiate a new one when the number running falls below 10.

curl -s http://www.commandlinefu.com/commands/browse|egrep '("Fin.*and"|<div class="command">.*</div>)'|sed 's/<[^<]*>//g'|ruby -rubygems -pe 'require "cgi"; $_=sprintf("\n\n%-100s\n\t#%-20s",CGI.unescapeHTML($_).chomp.strip, gets.lstrip) if $.%2'

2009-08-18 19:04:03

User: copremesis

Functions: egrep sed

Up
Down

Scrape commands from commandline fu's 1st page

just bored here at work ... if your are daring ... add '| bash' .... enjoy

require 'ruby'

diff <(cd /path-1; find . -type f -print | egrep -i '\.m4a$|\.mp3$') <(cd /path-2; find . f -print | egrep -i '\.m4a$|\.mp3$')

2009-08-17 00:49:31

User: drewk

Functions: cd diff egrep find

Up
Down

diff will usually only take one file from STDIN. This is a method to take the result of two streams and compare with diff. The example I use to compare two iTunes libraries but it is generally applicable.

diff is designed to compare two files. You can also compare directories. In this form, bash uses 'process substitution' in place of a file as an input to diff. Each input to diff can be filtered as you choose. I use find and egrep to select the files to compare.

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

‹ First < 3 4 5 6 7 >