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2011-03-12 - Confoo 2011 presentation
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Commands using grep from sorted by
Terminal - Commands using grep - 1,518 results
svn log | grep "bodge\|fudge\|hack\|dirty"
2009-05-15 09:55:44
User: root
Functions: grep

A good way to understand what you've let yourself in for. Potential project metric could be the count:

svn log | grep -c "bodge\|fudge\|hack\|dirty"
svn st | grep '^\?' | awk '{print $2}' | xargs svn add; svn st | grep '^\!' | awk '{print $2}' | xargs svn rm
2009-05-14 14:34:50
User: stedwick
Functions: awk grep xargs

automatically add and remove files in subversion so that you don't have to do it through the annoying svn commands anymore

curl -s http://checkip.dyndns.org/ | grep -o "[[:digit:].]\+"
grep -i '<searchTerm>\|<someOtherSearchTerm>' <someFileName>
2009-05-11 23:05:54
User: scifisamurai
Functions: grep

This is a simple but useful command to search for multiple terms in a file at once. This prevents you from having to do mutliple grep's of the same file.

echo 2006-10-10 | grep -c '^[0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9]$'
2009-05-11 22:18:43
User: rez0r
Functions: echo grep

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.

curl -s http://bash.org/?random1|grep -oE "<p class=\"quote\">.*</p>.*</p>"|grep -oE "<p class=\"qt.*?</p>"|sed -e 's/<\/p>/\n/g' -e 's/<p class=\"qt\">//g' -e 's/<p class=\"qt\">//g'|perl -ne 'use HTML::Entities;print decode_entities($_),"\n"'|head -1
2009-05-07 13:13:21
User: Iftah
Functions: grep head perl sed

bash.org is a collection of funny quotes from IRC.

WARNING: some of the quotes contain "adult" jokes... may be embarrassing if your boss sees them...

Thanks to Chen for the idea and initial version!

This script downloads a page with random quotes, filters the html to retrieve just one liners quotes and outputs the first one.

Just barely under the required 255 chars :)


You can replace the head -1 at the end by:

awk 'length($0)>0 {printf( $0 "\n%%\n" )}' > bash_quotes.txt

which will separate the quotes with a "%" and place it in the file.

and then:

strfile bash_quotes.txt

which will make the file ready for the fortune command

and then you can:

fortune bash_quotes.txt

which will give you a random quote from those in the downloaded file.

I download a file periodically and then use the fortune in .bashrc so I see a funny quote every time I open a terminal.

for i in *jpg; do jpeginfo -c $i | grep -E "WARNING|ERROR" | cut -d " " -f 1 | xargs -I '{}' find /mnt/sourcerep -name {} -type f -print0 | xargs -0 -I '{}' cp -f {} ./ ; done
2009-05-07 00:30:36
User: vincentp
Functions: cp cut find grep xargs

Find all corrupted jpeg in the current directory, find a file with the same name in a source directory hierarchy and copy it over the corrupted jpeg file.

Convenient to run on a large bunch of jpeg files copied from an unsure medium.

Needs the jpeginfo tool, found in the jpeginfo package (on debian at least).

lsof -i | grep -i estab
find . -name "*.[ch]" -exec grep -i -H "search pharse" {} \;
2009-05-06 15:22:49
User: bunedoggle
Functions: find grep
Tags: find grep

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

awk -F\" '{print $4}' *.log | grep -v "eviljaymz\|\-" | sort | uniq -c | awk -F\ '{ if($1>500) print $1,$2;}' | sort -n
2009-05-05 22:21:04
User: jaymzcd
Functions: awk grep sort uniq

This prints a summary of your referers from your logs as long as they occurred a certain number of times (in this case 500). The grep command excludes the terms, I add this in to remove results Im not interested in.

lynx -dump randomfunfacts.com | grep -A 3 U | sed 1D
2009-05-05 07:52:10
User: xizdaqrian
Functions: grep sed

This is a working version, though probably clumsy, of the script submitted by felix001. This works on ubuntu and CygWin. This would be great as a bash function, defined in .bashrc. Additionally it would work as a script put in the path.

wget -q -O- http://www.gutenberg.org/dirs/etext96/cprfd10.txt | sed '1,419d' | tr "\n" " " | tr " " "\n" | perl -lpe 's/\W//g;$_=lc($_)' | grep "^[a-z]" | awk 'length > 1' | sort | uniq -c | awk '{print $2"\t"$1}'
2009-05-04 16:00:39
User: alperyilmaz
Functions: awk grep perl sed sort tr uniq wget

This command might not be useful for most of us, I just wanted to share it to show power of command line.

Download simple text version of novel David Copperfield from Poject Gutenberg and then generate a single column of words after which occurences of each word is counted by sort | uniq -c combination.

This command removes numbers and single characters from count. I'm sure you can write a shorter version.

p=$(netstat -nate 2>/dev/null | awk '/LISTEN/ {gsub (/.*:/, "", $4); if ($4 == "4444") {print $8}}'); for i in $(ls /proc/|grep "^[1-9]"); do [[ $(ls -l /proc/$i/fd/|grep socket|sed -e 's|.*\[\(.*\)\]|\1|'|grep $p) ]] && cat /proc/$i/cmdline && echo; done
2009-04-30 12:39:48
User: j0rn
Functions: awk cat grep ls netstat sed

Ok so it's rellay useless line and I sorry for that, furthermore that's nothing optimized at all...

At the beginning I didn't managed by using netstat -p to print out which process was handling that open port 4444, I realize at the end I was not root and security restrictions applied ;p

It's nevertheless a (good ?) way to see how ps(tree) works, as it acts exactly the same way by reading in /proc

So for a specific port, this line returns the calling command line of every thread that handle the associated socket

ps auxf | grep httpd | grep -v grep | grep -v defunct | awk '{sum=sum+$6}; END {print sum/1024}'
dpkg-query -l| grep -v "ii " | grep "rc " | awk '{print $2" "}' | tr -d "\n" | xargs aptitude purge -y
2009-04-28 19:25:53
User: thepicard
Functions: awk grep tr xargs

This will, for an application that has already been removed but had its configuration left behind, purge that configuration from the system. To test it out first, you can remove the last -y, and it will show you what it will purge without actually doing it. I mean it never hurts to check first, "just in case." ;)

sudo aptitude purge `dpkg --get-selections | grep deinstall | awk '{print $1}'`
sudo apt-get remove --purge `dpkg -l | awk '{print $2}' | grep gnome` && apt-get autoremove
2009-04-28 10:34:42
User: kelevra
Functions: awk grep sudo
Tags: awk apt-get dpkg

Useful for removes a package and its depends, for example to remove the gnome desktop environment, also configuration files will be removed, you should be carefully and sure that you want to do this.

lspci |grep VGA
2009-04-28 08:34:42
User: CafeNinja
Functions: grep lspci
Tags: video Ubuntu

Displays only the VGA adapter/chipset being used for the graphics. In this case, it gave me the "M22" and "Mobility Radeon x300" that I needed to research a graphics issue I was having.

netstat -an | grep ESTABLISHED | awk '{print $5}' | awk -F: '{print $1}' | sort | uniq -c | awk '{ printf("%s\t%s\t",$2,$1) ; for (i = 0; i < $1; i++) {printf("*")}; print "" }'
2009-04-27 22:02:19
User: knassery
Functions: awk grep netstat sort uniq

Written for linux, the real example is how to produce ascii text graphs based on a numeric value (anything where uniq -c is useful is a good candidate).

grep -i --color=auto
2009-04-27 15:03:28
User: P17
Functions: grep

Highlights the search pattern in red.

for i in /sys/class/net/*; do e=`basename $i`; echo "# $e"; sudo ethtool $e | grep -E "Link|Speed" ; done
2009-04-25 14:32:08
User: hank
Functions: echo grep sudo
Tags: Network Linux

Basically an improvement on an earlier ethtool command line.

for M in 0 1 2 3 ; do echo eth$M ;/sbin/ethtool eth$M | grep -E "Link|Speed" ; done
2009-04-22 19:32:41
User: Wubby
Functions: echo grep

Give the Speed and Link status of eth# 0-3. This is sort of what mii-tool does, but eth-tool is better, yet lacks device discovery.

screen -ls | grep pts | gawk '{ split($1, x, "."); print x[1] }' | while read i; do gnome-terminal -e screen\ -dx\ $i; done
2009-04-22 10:36:39
User: microft
Functions: gawk grep read screen

connects to all the screen instances running.

emerge -epv world | grep USE | cut -d '"' -f 2 | sed 's/ /\n/g' | sed '/[(,)]/d' | sed s/'*'//g | sort | uniq > use && grep ^- use | sed s/^-// | sed ':a;N;$!ba;s/\n/ /g' > notuse && sed -i /^-/d use && sed -i ':a;N;$!ba;s/\n/ /g' use
2009-04-19 07:54:08
User: Keruspe
Functions: cut grep sed sort uniq
Tags: Gentoo emerge USE

This command puts all the flags of the USE variable actually used by the packages you emerged to the file "use", and those which are unused but available to the file "notuse"

xmms2 mlib search NOT +rating | grep -r '^[0-9]' | sed -r 's/^([0-9]+).*/\1/' | sort -R | head | xargs -L 1 xmms2 addid
2009-04-16 20:27:30
Functions: grep head sed sort xargs

If you're like me and want to keep all your music rated, and you use xmms2, you might like this command.

I takes 10 random songs from your xmms2 library that don't have any rating, and adds them to your current playlist. You can then rate them in another xmms2 client that supports rating (I like kuechenstation).

I'm pretty sure there's a better way to do the grep ... | sed ... part, probably with awk, but I don't know awk, so I'd welcome any suggestions.