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Commands tagged grep from sorted by
Terminal - Commands tagged grep - 350 results
pcregrep --color -M -N CRLF "owa_pattern\.\w+\W*\([^\)]*\)" source.sql
sed '/'"<opening tag>"'/,/'"<closing tag>"'/{/'"<closing tag>"'/d;p};d' "<file>"
cat file.txt | sed -e /<opening tag>/d -e /<closing tag>/G | sed -e '/./{H;$!d;}' -e 'x;/<string to search>/!d;'
2010-11-04 10:31:15
User: EBAH
Functions: cat sed
2

Working with log files that contains variable length messages wrapped between open and close tags it may be useful to filter the messages upon a keyword.

This works fine with GNU sed version 4.2 or higher, so pay attention to some unix distros (solaris, hp-ux, etc.).

Linux should be ok.

GREP_OPTIONS='-D skip --binary-files=without-match --ignore-case'
2010-11-03 23:10:09
User: AskApache
7

This is very helpful to place in a shell startup file and will make grep use those options all the time. This example is nice as it won't show those warning messages, skips devices like fifos and pipes, and ignores case by default.

grep -i '[^script$]' 1.txt
curl -s http://urlxray.com/display.php?url=http://tinyurl.com/demo-xray | grep -o '<title>.*</title>' | sed 's/<title>.*--> \(.*\)<\/title>/\1/g'
2010-09-30 10:25:18
User: karpoke
Functions: grep sed
Tags: sed grep curl
-3

We can put this inside a function:

fxray() { curl -s http://urlxray.com/display.php?url="$1" | grep -o '<title>.*</title>' | sed 's/<title>.*--> \(.*\)<\/title>/\1/g'; }; fxray http://tinyurl.com/demo-xray
pgrep -c cat
find . -name "*noticia*" -name "*jhtm*" -name "*.tpl" -exec grep -li "id=\"col-direita\"" '{}' \; | xargs -n1 mate
grep -ZlRr -e BAD_SCRIPT_LINE * |xargs -0 sed -i 's/BAD_SCRIPT_LINE//g'
2010-08-30 22:12:57
User: homoludens
Functions: grep sed xargs
0

recursive find and replace. important stuff are grep -Z and zargs -0 which add zero byte after file name so sed can work even with file names with spaces.

marbles () { c=''; for i in $(seq $1); do c+='{b,r}'; done; x=$(eval echo $c); p=''; for i in $(seq $2); do p+='b*r'; done; y=$(grep -wo "${p}b*" <<< $x); wc -l <<< "$y"; grep -vc 'rr' <<< "$y"; }
2010-08-27 23:04:33
User: quintic
Functions: echo eval grep seq wc
-4

Suppose you have 11 marbles, 4 of which are red, the rest being blue. The marbles are indistinguishable, apart from colour. How many different ways are there to arrange the marbles in a line? And how many ways are there to arrange them so that no two red marbles are adjacent?

There are simple mathematical solutions to these questions, but it's also possible to generate and count all possibilities directly on the command line, using little more than brace expansion, grep and wc!

The answer to the question posed above is that there are 330 ways of arranging the marbles in a line, 70 of which have no two red marbles adjacent. See the sample output.

To follow the call to marbles 11 4: after c=''; for i in $(seq $1); do c+='{b,r}'; done;, $c equals {b,r}{b,r}{b,r}{b,r}{b,r}{b,r}{b,r}{b,r}{b,r}{b,r}{b,r}

After x=$(eval echo $c), and brace expansion, $x equals bbbbbbbbbbb bbbbbbbbbbr ... rrrrrrrrrrb rrrrrrrrrrr, which is all 2^11 = 2048 strings of 11 b's and r's.

After p=''; for i in $(seq $2); do p+='b*r'; done;, $p equals b*rb*rb*rb*r

Next, after y=$(grep -wo "${p}b*"

Finally, grep -vc 'rr'

git grep "search for something" $(git log -g --pretty=format:%h -S"search for something")
grep -a -B 25 -A 100 'some string in the file' /dev/sda1 > results.txt
2010-08-19 20:07:42
User: olalonde
Functions: grep
22

grep searches through a file and prints out all the lines that match some pattern. Here, the pattern is some string that is known to be in the deleted file. The more specific this string can be, the better. The file being searched by grep (/dev/sda1) is the partition of the hard drive the deleted file used to reside in. The ?-a? flag tells grep to treat the hard drive partition, which is actually a binary file, as text. Since recovering the entire file would be nice instead of just the lines that are already known, context control is used. The flags ?-B 25 -A 100? tell grep to print out 25 lines before a match and 100 lines after a match. Be conservative with estimates on these numbers to ensure the entire file is included (when in doubt, guess bigger numbers). Excess data is easy to trim out of results, but if you find yourself with a truncated or incomplete file, you need to do this all over again. Finally, the ?> results.txt? instructs the computer to store the output of grep in a file called results.txt.

Source: http://spin.atomicobject.com/2010/08/18/undelete?utm_source=y-combinator&utm_medium=social-media&utm_campaign=technical

svn status | grep "^\?" | awk '{print $2}' | xargs svn add
2010-08-14 18:56:15
User: kureikain
Functions: awk grep xargs
Tags: svn awk grep
1

When working on a big proeject with SVN, you create quite much files, for now! Can just sit here and type svn add for all of them!

svn status will return a list of all of file which get ?(not add), "M"(Modified), "D"(Deleted)! This code just grep "?" flag, then add it into SVN again!

ls -Xp /path/to/dir | grep -Eo "\.[^/]+$" | uniq
2010-08-12 16:32:54
User: karpoke
Functions: grep ls
Tags: uniq ls grep
0

If we want files with more than one extension, like .tar.gz, only appear the latest, .gz:

ls -Xp /path/to/dir | grep -Eo "\.[^./]+$" | uniq
find /path/to/dir -type f | grep -o '\.[^./]*$' | sort | uniq
svn st | grep -e '^M' | awk '{print $2}' | xargs svn revert
netstat -rn | grep UG | tr -s " " | cut -d" " -f2
find . -name '*.txt' -print0 | parallel -0 -j+0 lzma
2010-07-28 21:01:12
Functions: find
Tags: find grep lzma
2

This will deal nicely with filenames containing newlines and will run one lzma process per CPU core. It requires GNU Parallel http://www.youtube.com/watch?v=OpaiGYxkSuQ

find . -name '*.txt' | grep -v '\.lzma$' | xargs -n 1 lzma -f -v -3
rm $( ls | egrep -v 'abc|\s' )
2010-07-18 10:59:15
User: dbbolton
Functions: egrep ls rm
Tags: grep rm
-1

Really, you deserve whatever happens if you have a whitespace character in a file name, but this has a small safety net. The truly paranoid will use '-i'.

alias dush="du -xsm * | sort -n | awk '{ printf(\"%4s MB ./\",\$1) ; for (i=1;i<=NF;i++) { if (i>1) printf(\"%s \",\$i) } ; printf(\"\n\") }' | tail"
2010-07-15 10:38:27
User: dopeman
Functions: alias
-1

Essentially the same as funky's alias, but will not traverse filesystems and has nicer formatting.

grep -R --include=*.cpp --include=*.h --exclude=*.inl.h "string" .
2010-07-14 16:32:28
User: sweinst
Functions: grep
Tags: find xargs grep
0

Gnu grep allows to restrict the search to files only matching a given pattern. It also allows to exclude files.

find . -name '*.?pp' -exec grep -H "string" {} \;
find . -name '*.?pp' | xargs grep -H "string"
2010-07-14 14:41:07
User: cout
Functions: find grep xargs
Tags: find xargs grep
2

I like this better than some of the alternatives using -exec, because if I want to change the string, it's right there at the end of the command line. That means less editing effort and more time to drink coffee.

grep -i '^DocumentRoot' /etc/httpd/conf/httpd.conf | cut -f2 -d'"'