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Commands tagged grep from sorted by
Terminal - Commands tagged grep - 354 results
grep -rc logged_in app/ | cut -d : -f 2 | awk '{sum+=$1} END {print sum}'
2009-07-15 14:16:44
User: terceiro
Functions: awk cut grep
-2

grep's -c outputs how may matches there are for a given file as "file:N", cut takes the N's and awk does the sum.

vim $(grep test *)
2009-07-15 10:15:04
User: goatboy
Functions: grep test vim
Tags: vim grep
4

I often use "vim -p" to open in tabs rather than buffers.

export LANG=C; grep string longBigFile.log
2009-07-14 12:48:02
User: ioggstream
Functions: export grep
Tags: grep LANG
0

greps using only ascii, skipping the overhead of matching UTF chars.

Some stats:

$ export LANG=C; time grep -c Quit /var/log/mysqld.log

7432

real 0m0.191s

user 0m0.112s

sys 0m0.079s

$ export LANG=en_US.UTF-8; time grep -c Quit /var/log/mysqld.log

7432

real 0m13.462s

user 0m9.485s

sys 0m3.977s

Try strace-ing grep with and without LANG=C

grep <pattern> -R . --exclude-dir='.svn'
fmiss() { grep -RL "$*" * }
2009-07-13 18:30:54
User: inkel
Functions: grep
Tags: grep
1

This one would be much faster, as it's only one executed command.

(curl -d q=grep http://www.commandlinefu.com/search/autocomplete) | egrep 'autocomplete|votes|destination' | perl -pi -e 's/a style="display:none" class="destination" href="//g;s/<[^>]*>//g;s/">$/\n\n/g;s/^ +//g;s/^\//http:\/\/commandlinefu.com\//g'
2009-07-08 22:10:49
User: isaacs
Functions: egrep perl
1

There's probably a more efficient way to do this rather than the relatively long perl program, but perl is my hammer, so text processing looks like a nail.

This is of course a lot to type all at once. You can make it better by putting this somewhere:

clf () { (curl -d "q=$@" http://www.commandlinefu.com/search/autocomplete 2>/dev/null) | egrep 'autocomplete|votes|destination' | perl -pi -e 's/<a style="display:none" class="destination" href="//g;s/<[^>]*>//g;s/">$/\n\n/g;s/^ +|\([0-9]+ votes,//g;s/^\//http:\/\/commandlinefu.com\//g'; }

Then, to look up any command, you can do this:

clf diff

This is similar to http://www.colivre.coop.br/Aurium/CLFUSearch except that it's just one line, so more in the spirit of CLF, in my opinion.

find . -not \( -name .svn -prune \) -type f -print0 | xargs --null grep <searchTerm>
2009-07-08 20:08:05
User: qazwart
Functions: find grep xargs
Tags: find xargs grep
8

By putting the "-not \( -name .svn -prune \)" in the very front of the "find" command, you eliminate the .svn directories in your find command itself. No need to grep them out.

You can even create an alias for this command:

alias svn_find="find . -not \( -name .svn -prune \)"

Now you can do things like

svn_find -mtime -3
echo alias grep=\'grep --color=auto\' >> ~/.bashrc ; . ~/.bashrc
2009-07-05 07:44:13
User: 0x2142
Functions: alias echo
Tags: color grep
7

This will create a permanent alias to colorize the search pattern in your grep output

sed -n '/START/,${/STOP/q;p}'
2009-06-19 15:27:36
User: mungewell
Functions: sed
Tags: sed grep
3

GNU Sed can 'address' between two regex, but it continues parsing through to the end of the file. This slight alteration causes it to terminate reading the input file once the STOP match is made.

In my example I have included an extra '/START/d' as my 'start' marker line contains the 'stop' string (I'm extracting data between 'resets' and using the time stamp as the 'start').

My previous coding using grep is slightly faster near the end of the file, but overall (extracting all the reset cycles in turn) the new SED method is quicker and a lot neater.

grep -v "^\W$" <filename>
2009-06-18 08:17:22
User: nikc
Functions: grep
Tags: grep non-empty
0

I had some trouble removing empty lines from a file (perhaps due to utf-8, as it's the source of all evil), \W did the trick eventually.

grep -2 -iIr "err\|warn\|fail\|crit" /var/log/*
2009-06-17 19:41:04
User: miketheman
Functions: grep
6

Using the grep command, retrieve all lines from any log files in /var/log/ that have one of the problem states

grep -h -o '<[^/!?][^ >]*' * | sort -u | cut -c2-
2009-06-17 00:22:18
User: thebodzio
Functions: cut grep sort
Tags: sort grep cut
2

This set of commands was very convenient for me when I was preparing some xml files for typesetting a book. I wanted to check what styles I had to prepare but coudn't remember all tags that I used. This one saved me from error-prone browsing of all my files. It should be also useful if one tries to process xml files with xsl, when using own xml application.

for k in `git branch|perl -pe s/^..//`;do echo -e `git show --pretty=format:"%Cgreen%ci %Cblue%cr%Creset" $k|head -n 1`\\t$k;done|sort -r
2009-06-03 08:25:00
User: brunost
Functions: echo head perl sort
15

Print out list of all branches with last commit date to the branch, including relative time since commit and color coding.

egrep -o '[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}' file.txt
svn log fileName|cut -d" " -f 1|grep -e "^r[0-9]\{1,\}$"|awk {'sub(/^r/,"",$1);print "svn cat fileName@"$1" > /tmp/fileName.r"$1'}|sh
2009-05-27 02:11:58
User: fizz
Functions: awk cut grep
Tags: bash svn awk grep
2

exported files will get a .r23 extension (where 23 is the revision number)

curl -s checkip.dyndns.org | grep -Eo '[0-9\.]+'
2009-05-21 16:12:21
User: haivu
Functions: grep
4

The curl command retrieve the HTML text containing the IP address. The grep command picks out the IP address from that HTML text.

grep --color=always | less -R
2009-05-20 20:30:19
User: dinomite
Functions: grep less
31

Get your colorized grep output in less(1). This involves two things: forcing grep to output colors even though it's not going to a terminal and telling less to handle those properly.

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
-1

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.

find . -name "*.[ch]" -exec grep -i -H "search pharse" {} \;
2009-05-06 15:22:49
User: bunedoggle
Functions: find grep
Tags: find grep
33

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

lynx -dump randomfunfacts.com | grep -A 3 U | sed 1D
2009-05-05 07:52:10
User: xizdaqrian
Functions: grep sed
0

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.

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
-5

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

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
-3

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." ;)

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
3

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.

locate searchstring | xargs grep foo
2009-04-16 12:51:24
User: zimon
Functions: grep locate xargs
Tags: grep locate
-2

Greps located files for an expression.

Example greps all LaTeX files for 'foo':

locate *.tex | xargs grep foo

To avoid searching thousands of files with grep it could be usefull to test first how much files are returned by locate:

locate -c *.tex
alias lg='ls --color=always | grep --color=always -i'
2009-04-11 23:15:12
User: kFiddle
Functions: alias grep
Tags: ls alias color grep
6

This is a simple command, but extremely useful. It's a quick way to search the file names in the current directory for a substring. Normally people use "ls *term*" but that requires the stars and is not case insensitive. Color (for both ls and grep) is an added bonus.