grep is a command-line tool for searching text patterns in files

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Linux: Does find | xargs grep have limitations?

I've historically performed something like: find . 2>/dev/null | xargs grep -i something_to_find 2>/dev/null If my pwd is barfoo (/foo/bar/baz/foofoo/foobar/foobaz/barfoo) it finds matches. ...
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Regex/pattern matching problem to extract data

What is the best way to remove distances in the following lines and output cdv format. Can this be done reasonably easily on the command line? I'd like to avoid having to write a full-blow script. ...
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426 views

Most efficient grep method

Currently I am grepping data from a file containing any of the following: ...
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486 views

Extract integers enclosed in round brackets

I'm new to Linux. I've a file which contains list of movie names and their release year. I want to list out all release years. Specifically my file looks like below TDKR(2012) Vicky Cristina ...
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Parse apache logs to exclude IP ranges

I need to look for some requests in a huge pile of apache logs. My only requirement is this: I need to only view the requests coming from any IP address that is NOT included in a list of 50 IP ranges ...
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When is it useful to use “grep — SOMEPATTERN”?

So under Linux/AIX where ever.., when is it useful to use: grep -- SOMEPATTERN the Question is the "--" part. When is it usefull to use?
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How to detect dos format files in git bash

Git Bash is a nice bash shell you get in Windows as part of the installation of Git. It comes with other typical unix tools bundled inside, such as grep, sed, awk, perl. It doesn't have the file ...
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The simplest method to count lines matching specific patterns, including '0' if line is not found?

I have very big logs (several gigabytes per day), that can (but do not need to) contain specific lines. I have to count the number of occurences of every one of these lines on a daily basis. I have a ...
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3answers
730 views

Delete the matching line and several more from a file

I have a text file called file_a.txt. My first command is grep -A 12 ".production =" file_a.txt The output is a few block. Each block of string contains 13 rows I specifically want to delete all ...
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Generate “item tag” pairs from “item,item,…|tag” lists [closed]

The characteristics of the input data: Each line consists of two fields, separated by a pipe '|', where the first field is a comma-separated list of items, and the second field is a tag. Input ...
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Which is a better way to search- find with regex or find with grep?

Of these two ways of searching a file recursively in all the subdirectories, which is faster / better ? find . -regex ".*/.*abc.*" or find . | grep ".*abc.*"
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How can I grep a directory based on the contents of two successive lines?

How can I grep a directory for lines that contain "Foo", but only get matches when the next line also contains "Bar"?
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How can I enhance the output of find and grep?

I really don't look forward to having to do find/grep because the output, as returned by find . -exec grep sometext {} \; -print is just not very easy to read even when you dump it in a file. What ...
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How can I pass strings with single quotes to grep?

My desired outcome is the following: to recursively search a directory looking for a given string in all found files. The following command is my usual port of call: find ./ | xargs grep -ns 'foobar' ...
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bash merge 2 lists removing duplicated

I have an embedded linux system using Busybox (OpenWRT) - so commands are limited. I have two files that look like: first file aaaaaa bbbbbb cccccc mmmmmm nnnnnn second file mmmmmm nnnnnn ...
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how to grep for c:\

I'm using cygwin's grep to find all instances of hardcoded paths on c drive. doing: grep -r "c:\\" . gives grep: trailing backslash Does anybody know how I can do this?
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3answers
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Average rows with same first column

Given a file with two columns: Id ht 510 69 510 67 510 65 5l0 62 510 59 601 29 601 26 601 21 601 20 I need a way to coalesce all rows with the same ID into one that has an average height. In this ...
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3answers
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Online grep exercises?

Are there any online grep tutorials that would feature some online tool for performing exercises? For example, having some predefined text sample and being told what patterns to find and so forth? It ...
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Why does grep not work with redirection?

Using the top command with redirection works fine: top > top.log Now I want to use grep to filter a certain line: top | grep "my_program" > top.log But the log file will remain empty. But ...
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Need to grep file with specific letter and move to another folder linux

I need to select files which contain "Error" or "traffic" in their names, e.g. abc_ERRor.csv raError.csv bsn_Error.csv bbbctraffic.csv ccc_traffic.csv ... and move them into corresponding ...
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Searching for a string on multiple zip files.

I have a folder that contains about 200 zip files. Each zip file contains only one text file in it. I would like to search for a specific string in all the text files in all the zip files. I tried ...
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352 views

Use command grep and locate

How I can make the grep command locate certain words in the files specified by the routes found by the locate command? locate my.cnf | grep user (I want that grep command search the word "user" ...
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1answer
161 views

grep for n or more periods on a given line

I want to be able to arbitrarily match lines that contain a lot of periods, like this: $ echo "there's. someone on the wing. some. thing." | grep -stuFF [[:idunno:]]{4,} there's. someone on the wing. ...
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compare two files get identical list

file1.txt (50 lines) TERYUFV00000010753 TERYUFV00000009526 file2.txt (500 lines) TERYUFV00000009526 refids_739_known_8/10_target TERYUFV00000018907 refids_12023_known_21/22_target ...
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Display lines inbetween text with grep

I know that I can use the -A and -B command for grep to get a lot of what I am looking for however that is not quite what I want. I am looking to parse the httpd.conf file to search for a domain. ...
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Need to parse a double entry table with two pairs

I have this two-entry table resulting from a program output: Variable1 : Value1 Variable2 : Value2 Variable3 : Value3 Variable4 : Value4 Variable5 : Value5 Variable6 : Value6 ...
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1answer
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Find and remove many files by specific content [duplicate]

Possible Duplicate: Arg list too long error while using find I try to find many files in many folders with specific content, and delete them. find dir.*/* -exec grep -l "content" {} \; | ...
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Piping from grep to awk not working

I am trying to grep the ongoing tail of file log and get the nth word from a line. Example file: $ cat > test.txt <<EOL Beam goes blah John goes hey Beam goes what? John goes forget it Beam ...
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1answer
263 views

grep list of names and information from bigger file

I have two files: one with list of names (500 entries) and other having some more information for each entry in A.txt and extra entries too. File A.txt (each line is starting with > (fasta format) ...
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2answers
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reformat a text file to have all text on one line using CentOS 5.6

I have a 210-line block of HTML that I have stored in a HTML for debugging purposes. The HTML, as you would expect, is formatted accordingly so is stored in the file with spaces and tabs. Is it ...
4
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1answer
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Delete last character in a word but only if the character is there - in bash

How to remove last character only if it's there? input: OpenOffice.org/m openOffice.org/ozm Pers. Pfg. phil. Prof. resp. Roonstr./m roonstr./ozm desired output: OpenOffice.org openOffice.org ...
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How to display line number while doing grep on a file

How to display line number while doing grep on a file. For example: grep CONFIG_PM_ADVANCED_DEBUG /boot/config-`uname -r
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Finding out how many programs I have not installed from a list with grep/awk in archlinux

I want to see how many packages from a list are not installed. I use archlinux, so I use pacman -Q to determine if a package is installed. If it is not installed, it returns a message like: "error: ...
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1answer
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grep --color adds ANSI code ESC[K - This can change displayed text

Why does grep add ANSI code \e[K to its colored output? I can't see the point of it, but obviously the developers can. It is an ANSI/VT100 Terminal code which is used to "Clear line from current ...
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1answer
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Bash, remove lines containing string with grep

This is currently deleting the whole contents of the file in question: #!/bin/bash rpc_port="9201"; dir="/etc/apache2/ports.conf" cat $dir | grep -v "Listen $rpc_port" > $dir The file contents: ...
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How do I take a list and remove it from a file?

I have a long list of domain names that I need to remove from /etc/remotedomains. They're probably not in any particular order in the file. Each domain is on one line. How could I iterate through the ...
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3answers
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Why piping find and grep returns nothing?

I'm trying to have grep search inside specified files that are returned by find: find . -type d -name 'mydir*' -exec find '{}' -name '*.java' \; | grep 'MyClass' This doesn't work. Meanwhile, ...
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Pipe find into grep -v

I'm trying to find all files that are of a certain type and do not contain a certain string. I am trying to go about it by piping find to grep -v example: find -type f -name '*.java' | xargs grep -v ...
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1answer
531 views

Peculiar piping grep/head behavior

I'm helping the netadmin here with a perl regex to automate operating on some snapshots from our SAN and our scripts does stuff like this: varinit1=$(iscsiadm -m session | grep rbmsdata1 | head -n1 | ...
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1answer
268 views

PHP file recursive change array key on find [closed]

I used PHP array $lang['module']['1'] = 'Title'; $lang['module']['2'] = 'Title2'; $lang['value'] = 'text123'; how i can use replace in terminal Key Value to CASE UPPER ? $lang['VALUE'] ...
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Finding a substring in files across subdirectories with a single built-in command?

In Windows, if I wanted to find a string across all files in all subdirectories, I would do something like findstr /C:"the string" /S *.h However, in Linux (say, Ubuntu) I have found no other way ...
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1answer
506 views

How can I use unix tools with Cyrillic text?

I recently started processing Cyrillic text, and it's been really difficult. I couldn't get my Python scripts to work with it at all. And I tried. PHP worked well, but I don't know PHP. I just ...
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2answers
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How to do a regex search in a UTF-16LE file while in a UTF-8 locale?

EDIT: Due to a comment Warren Young made, it made me realize that I was not clear on one quite relevant point. My search string is already in UTF-16LE order (not in Unicode Codepoint order, which is ...
4
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5answers
616 views

grep second time faster

Suppose I do a time consuming recursive grep search. After seeing the results I want a different output; for example I want to add the option -C 3 for 3 context lines. I can do the whole search again ...
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3answers
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Grepping several lines from Nmap output

I apologize in advance as this is a simple question. So I'm attempting to scan a Class C to identify all mail servers by IP. The vast majority of IPs aren't mail servers. I'm trying to filter out the ...
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Is there any other way to use tail -f for grep -q && operation?

I found this solution: http://stackoverflow.com/questions/7178888/grep-q-not-exiting-with-tail-f but is there any other possible? UPD: I want to do tail -f | grep -q something && echo ...
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Grepping over a huge file performance

I have FILE_A which has over 300K lines and FILE_B which has over 30M lines. I created a bash script that greps each line in FILE_A over in FILE_B and writes the result of the grep to a new file. ...
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“Grep breaks, causing the boot process to hang forever”

Question within a question (from the Debian wiki): Should I use sid on my desktop? If you think you can handle a broken Debian system, sure. Do you know what to do if libpam0g breaks, ...
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1answer
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last modified with grep

I'd like to make a list to stdout of the files modified in the last two hours in the . directory using grep. It has to be automatic (can't ask user what time is it or similar stuff) and I have to use ...
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2answers
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Where does grep -r search by default?

I found if I search using grep without specifying a path, like grep -r 'mytext' it takes infinitely long. Meanwhile if I search with path specified grep -r 'mytext' . it instantly finds what I need. ...