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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.




Commands using egrep from sorted by
Terminal - Commands using egrep - 176 results
cat /etc/apache2/sites-enabled/* | egrep 'ServerAlias|ServerName' | tr -s " " | sed 's/^[ ]//g' | uniq | cut -d ' ' -f 2 | sed 's/www.//g' | sort | uniq
2010-04-08 08:51:17
User: chronosMark
Functions: cat cut egrep sed sort tr uniq

Get a list of all the unique hostnames from the apache configuration files. Handy to see what sites are running on a server.

ls | egrep -v "[REGULAR EXPRESSION]" | xargs rm -v
2010-04-01 02:40:40
User: Saxphile
Functions: egrep ls rm xargs
Tags: files rm

This is a slight variation of an existing submission, but uses regular expression to look for files instead. This makes it vastly more versatile, and one can easily verify the files to be kept by running ls | egrep "[REGULAR EXPRESSION]"

du -kd | egrep -v "/.*/" | sort -n
2010-03-30 15:40:35
User: rmbjr60
Functions: du egrep sort

Thanks for the submit! My alternative produces summaries only for directories. The original post additionally lists all files in the current directory. Sometimes the files, they just clutter up the output. Once the big directory is located, *then* worry about which file(s) are consuming so much space.

rpm --querytags | egrep -v HEADERIMMUTABLE | sort | while read tag ; do rpm -q --queryformat "$tag: [%{$tag} ]\n" -p $SomeRPMfile ; done
2010-03-25 05:40:48
Functions: egrep read rpm sort

If you want to relocate a package on your own, or you just want to know what those PREIN/UN and POSTIN/UN scripts will do, this will dump out all that detail simply.

You may want to expand the egrep out other verbose flags like CHANGELOGTEXT etc, as your needs require.

It isn't clear, but the formatting around $tag is important: %{$tag} just prints out the first line, while [%{$tag }] iterates thru multi-line output, joining the lines with a space (yes, there's a space between the g and } characters. To break it out for all newlines, use [%{$tag\n}] but the output will be long.

This is aside from rpm2cpio | cpio -ivd to extract the package files.

pattern='regexp_pattern'; find . -type f -perm +220 ! -name '*.bak' -print0 | xargs -0 egrep -lZ $pattern | xargs -0 sed -i.bak -e "/$pattern/d"
lsof -c $processname | egrep 'w.+REG' | awk '{print $9}' | sort | uniq
2010-02-24 16:47:49
User: alustenberg
Functions: awk egrep sort

lists all files that are opened by processess named $processname

egrep 'w.+REG' is to filter out non file listings in lsof, awk to get the filenames, and sort | uniq to remove duplciation

sudo aptitude update; sudo apt-get -y --print-uris upgrade | egrep -o -e "http://[^\']+" | sudo aria2c -c -d /var/cache/apt/archives -i -; sudo aptitude -y safe-upgrade
2010-02-18 16:02:29
User: freethinker
Functions: egrep sudo

Please install aria2c before you try the above command. On ubuntu the command to install aria2c would be:

sudo aptitude install aria2
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

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

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.

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

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 && egrep "00:00:00:00:00:00" /proc/net/arp
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
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
Functions: awk cut egrep grep

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

egrep -i "somepattern" `find . -type f -print`
find . -type f | perl -lne 'print if -T;' | xargs egrep "somepattern"
egrep 'https?://([[:alpha:]]([-[:alnum:]]+[[:alnum:]])*\.)+[[:alpha:]]{2,3}(:\d+)?(/([-\w/_\.]*(\?\S+)?)?)?'
2009-11-28 15:41:42
User: putnamhill
Functions: egrep

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.

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

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

lsmod | cut -d' ' -f1 | xargs modinfo | egrep '^file|^desc|^dep' | sed -e'/^dep/s/$/\n/g'
2009-11-17 02:13:34
User: mohan43u

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

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

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

egrep -v "^[[:blank:]]*($|#|//|/\*| \*|\*/)" somefile
find ~/Maildir/ -mindepth 1 -type d | egrep -v '/cur$|/tmp$|/new$' | xargs
tail -F file | egrep --color 'pattern|$'
tail -f file | egrep --color=always $\|PATTERN
2009-10-15 13:08:30
User: sitaram
Functions: egrep file tail
Tags: color

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

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