Regular expressions are a means of matching a pattern of characters within a string.

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Replacing string in all files found by grep. Can't get it to work

I'm trying to do what title says. So I find all needed files with grep: grep --include=\*.{php,ini,conf,sh} -ril -P "'([\d\w\-\_\.]+)(@domain.com)'" '/var/www_data/somepath/' Now I assume it's ...
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1answer
379 views

Why doesn't this regex work?

I want to look at the output of git status -s to determine whether there are any untracked files in the tree. I tried the following test, but the regex doesn't match. Why not? $ git status -s ## ...
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grep for an alphanumeric strings of any length with a colon on each side

How would you grep for an alphanumeric strings of 1 to 50 characters (ideally, any length would work too) with a colon on each side – a typical result would be all the lines containing the string ...
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1answer
94 views

find utility does not recognize bracket notation

I've two files in the current folder: submitWeb.m submit.m the following find does not show the two files: find . -regex .*submit\(Web\)?\.m But the above regex expression works fine in ...
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2answers
164 views

How to add a line in many files

I have many .html files and I need to add a meta tag after <head>'s start tag in each file. How I can do that? Can vim help me?
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191 views

Why isn't this sed regex matching?

I've recently started learning sed. I did $seq 10 | sed '/[^049]/d' I was expecting 4 9 10 as output. But I got 4 9 Where am I making mistake in understanding this regex?
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1answer
3k views

Grep - ^(\s*$) vs ^\s*$

I want to search for a field that only has spaces. When counting, this two commands gave me different results: grep "^\s*$" -E -c grep "^(\s*$)" -E -c Another thing. What is the correct way to say ...
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Why does my grep expression need to use $'string' to match tab characters?

If you take this code: echo -e '\t\t\tString' | grep '^[\t]*String' the result is blank because it doesn't match, yet this: echo -e '\t\t\tString' | grep $'^[\t]*String' works. I swear that I ...
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Extracting just a single group from a regular expression

I am trying to get a list of numbers from some hacked-together log files using zgrep. So, I am using: zgrep -ie "total time: .* ms" * This returns the whole line that I care about. I'd just like ...
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4k views

Get all regex matches between two patterns and print them to file

I've got a file with a bunch of long lines. I'd like to grab every group between two patterns and print them to a new file, one match per line. I could manage to do this with Python, but I'd prefer ...
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What does . match?

In working with regular expressions, I have been told that a dot character . will match everything. Except for newlines \n. Are there any other exceptions? What about the NUL character \0, or the ...
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719 views

Regex : how to verify that there are 13 greek letters with an odd number of consonants

Another regex that I can't seem to crack :( I tried with egrep '([qwrtzpsdfghjklxcvbnmy]{1})|([qwrtzpsdfghjklxcvbnmy]{3})|([qwrtzpsdfghjklxcvbnmy]{5})|([qwrtzpsdfghjklxcvbnmy]{7})' greek.txt ...
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1answer
106 views

Regex for crontab validation

I need to check in bash whether an entry into the crontab file is valid. Is there a crontab command switch? I can extract individual lines and try to control individual items through regex. But I ...
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1answer
90 views

Using sed to replace only the first two regex catches with different strings

So I'm trying to change two instances of a regex pattern to two different strings with sed like: sed -E "s/\\t([A-Za-z]|[-])+$/\\t`get_addr.py -1`/" /path/to/file.ext sed -E ...
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1answer
57 views

Problem with regular expression in gawk ('\<' not working)

I am trying to get into bash a little bit. I was going through this guide but the second example in this subsection on gawk doesn't seem to work. The problem is this command: ls -l | awk ...
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1answer
66 views

Accept only y or yes with a one-line regular expression

I want to check if an input is y or yes (inputs in lowercase) and reject everything else What I have now is ^y[e]{'0,1'}[s]['0,1']$ But this accepts y, ye, ys, yes. I don't want ye and ys to be ...
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How to perform a multiline grep across multiple files?

I'm trying to grab this pattern wherever it occurs in multiple log files (Note:these patterns can vary greatly in size, i.e. the amount of Blahs): Found an txt File Blah Blah 10019874 ...
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1answer
271 views

pcregrep newline lookbehind assertion bug?

Attempting to use pcregrep to print the first line after a blank line. For example, contents of file first line second line I need second line to be printed. Here are a few tests using the same ...
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1answer
152 views

Merging text files based on their filename

I have hundred of files with the following format: 2013_01_19_xyxyxyx.txt 2013_01_19_xyxyxyx.txt 2014_03_21_xyxyxyx.txt 2014_03_21_zxzxzxz.txt 2014_03_22_abababa.txt 2014_03_22_cbcbcbc.txt etc. I ...
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326 views

Replacing 3 or more digits with equivalent number of *

I want to replace any 3 or more digit string in a text file with equivalent number of *.For example: abc-1234-45 --> abc-****-45 echo "abc-1234-45" | sed 's/[0-9]\{3,\}/*/' I tried this but it only ...
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285 views

Expanding comma-separated list into separate lines

I have a file with some data in this form: Prefix text: First Name, Second Name, Third-- The prefix differs by line. The number of names varies from one to several. The suffix (-- in the example) ...
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How to insert both vimscript variable and string into vim search and replace

I've only just found out about Vimscript's existence as of today, so forgive me if this question is more basic than it seems, but I've been struggling to find an answer to this question for the better ...
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832 views

Using grep/sed/awk to classify log file entries

I need to process a very large log file with many lines in different formats. My goal is to extract unique line entries who have the same starting pattern, e.g. '^2011-02-21.*MyKeyword.*Error', ...
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36 views

Find repository names from gitolite info output

How do I extract the names from the gitolite info command output, for further piping into a script? I'm writing a migration script to migrate all my repositories from gitolite to a Gitlab server. ...
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1answer
172 views

How do back-references match in sed?

I found a one-line sed command on this site which removes duplicate entries in $PATH. There is one concept that I can't get my mind around. It uses saved matches in the match section to detect the ...
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1answer
332 views

Character classes: construct my own

I want to construct my own character class in a script, then modify (and use) it, for example: [:myclass:] contains a, *, \n (as linefeed) and [WHITESPACE]. I want to add all characters to ...
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How to block the Google Analytics Script using Privoxy

Related subject: Privoxy: blocking twitter, facebook and google outside of their domains + HTTPS Never mind what rule I am adding to the default.filter file, I don't make it to block these scripts. ...
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How can I exclude a string using a regular expression?

I have this file named test: http://edge.sharethis.com http://edge.sharethis.com https://timetosa.com http://timetosa.com https://webtest.es holahttp.com timetosa I want a expression that excludes ...
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220 views

Coloring tail output with perl

tail -f logfile.log | perl -pe 's/.*foo*/\e[1;41m$&\e[0m/g' will color all the lines containing the pattern "foo" in the logfile.log file. How can I make use of this in order to highlight ...
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Parsing Log Files with sed -e. Need to count unique class names

I have a file, let's call it filename.log, in it I have something like this (2014-11-18 14:09:21,766), , xxxxxx.local, EventSystem, DEBUG FtpsFile delay secs is 5 [pool-3-thread-7] (2014-11-18 ...
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How can I get the first column of a 300GB txt file?

let me first explain my problem in detail. It's actually pretty simple. I have a huge .txt file, 300GB to be more preciese, and I would like to put all the distinct strings from the first column, that ...
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Change filename from lowercase to uppercase recursively

I have 1,000,000 files in some folders and subfolders. I want to rename them from lowercase to uppercase using shell commands. I don't want to modify the extension. only filename part. I have found ...
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996 views

Wget - Mirroring a full website with requisites on differents hosts

I am trying to make a full static copy of a wordpress website with wget to be browsed without any network connection (all links and images must be converted). The different requisites for the pages ...
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300 views

Ex and Vi: buffers and regexes

I want to put regex matches to buffer but cannot get even simpler example y :.put myNewBuffer return msg [line] [put] [buffer] working ie how to put something to buffer? So to regular expressions ...
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How to use regrex with AWK for string replacement in this example? [duplicate]

Possible Duplicate: How to use regrex with AWK for string replacement in this example? Suppose there is some text from a file: (bookmarks ("Chapter 1 Introduction 1" "#1" ("1.1 Problem ...
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remove leading string in bash

I try getting this sed command to work. I have a string like rev00000010 and I only want the last number, 10 in that case. I have tried this: TEST='rev00000010' echo "$TEST" | sed ...
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260 views

Replace regex match with string containing match

I have a file with text as Afghanistan=+93 Albania=+355 Algeria=+213 American Samoa=+1 Andorra=+376 Angola=+244 It has all the country list and its dialing code. I want to replace: ...
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3answers
860 views

sed, grep, or tr command that returns only Latin characters from a UTF-8 file

I am working with the text of the 300 tang poems, which unfortunately is a single file containing both Chinese and English. Since I am interested in 'extracting' the English, I hope to use sed, ...
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sed one-liner to delete any line that begins with a digit

Pretend I am working with this file. The beginning of the first visible line is obscured, so ignore that. 43 is the beginning of the next line, and that line would be deleted. The next line (which ...
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5answers
282 views

Duplicate lines and make them unique?

I have the following structure of text lines: 3923 001 L05 LV,L05 RM 3923 002 L12 RA,L12 LA 3923 003 I06 ALL 3923 004 G04 RV,Z09 ALL but i would need this: 3923 001 L05 LV 3923 001 ...
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Can tr work with regex?

I have a file like this: AAAA BBBB CCCC DDDD etc Words in separate lines. I want to add them quotes using tr. So I tried the following: 1) To add a quote in the start of each word ...
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How to find files with a certain subpath?

I need to find all xml-files that are placed in folders named config. Also config must be somewhere under a folder named trunk. For example, I am interested in all files like below: ...
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Escaping * with Regular Expressions and Grep

I have a file that has unique lines that start with 2 stars (**). However when I run a grep command for grep \*\* fileName I get all of the lines in the file. This is very unusual, and what I ...
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SED command not replacing (working regex)

I'm trying to replace in one of my projects all mysql to mysqli, with their parameters. To do so, I'm searching for all files with mysql in my folder recursively and replacing it with mysqli. Ex: ...
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How can I remove lines matching foo but not matching bar?

Assume I want to remove the 2nd and 3rd, but not the 4th line in the following file (those which match foo but do not match bar), can I easily do this with e.g. sed? text foo some more text even more ...
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Apply item replacement inside enumerate in Perl regex?

Data 7. Masi is the same as \begin{enumerate} A B ABC ha lorem \end{enumerate} 1. ABC is \begin{enumerate} P B Lorem maam \end{enumerate} which I want to be 7. Masi is the same as ...
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Extract IP address from a string

The Linux host command returns: hostA.domain.com has address xx.xxx.xxx.xx How do I get just the IP address and put it in the $ipaddr variable? open(FILE, "hostlist.txt") or die("Unable to open ...
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Why don't I need to escape a character class in sed but I need to escape the rest?

I am confused with sed. I had a file with the following contents: [ 2014/02/10 14:45:15 | INFO ] Saving data for customer: 273667 [ 2014/02/10 14:45:15 | INFO ] Saving data for customer: ...
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SED change only start of line and preserve end of line

Basically I have a situation where I frequently need to modify my hosts file to access different servers at my workplace. In an attempt to automate the process. I've been trying to use sed to make the ...
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Pulling out keywords using standard command line utilities?

As an example, this is the pronunciation of "when" according to Wiktionary. enPR, IPA and X-SAMPA are different schemes for showing pronunciations. when:* {{a|US}} {{enPR|wĕn|hwĕn}}, ...