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

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How to reverse-match a string in the Vim programming language?

I want to find the last index of any character in the [abc] set in the abcabc string but the search should start from the end of the string: " Returns the 0th index but I want the 5th. let ...
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2answers
1k views

extract last match from logfile till end

Using sed, grep, awk, or ruby, what's a simple way to find the last match of a string in a larger log file, and send every line following it (inclusive) to another file? Example: grep -A222 ...
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2answers
869 views

Regex for phrase matching with case statement in ksh

I am trying to start or stop a service on AIX in ksh. I am trying to start to build in fool proofing for checking things like if the services is already down, etc. Here is my script #!/bin/ksh ...
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2answers
358 views

How can I find matches with sed (or similar) for configuration parameters?

I'm pretty good at using php's preg_match (and similar) commands, and I'm also pretty good with regular expressions, but I don't do very well with sed. I have two shell scripts I'm working on and I'd ...
2
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1answer
178 views

grep all words with specified length, without letter x

So I am stuck here: grep -E '^....c...c...$' shows all words with the expr I need. Now from this words I only need the ones that don't have a x. Who can help me?
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Print lines where first field has only four characters using regex in awk?

John Goldenrod:(916) 348-4278:250:100:175 Chet Main:(510) 548-5258:50:95:135 Tom Savage:(408) 926-3456:250:168:200 Elizabeth Stachelin:(916) 440-1763:175:75:300 output should contain the lines ...
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2answers
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Removing Color Codes From Output [duplicate]

Possible Duplicate: Removing control chars (including console codes / colours) from script output I'm working on a script to work alongside a program that I'm writing. What i'm trying to do ...
11
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2answers
5k views

How to run grep with multiple AND patterns?

I would like to get the multi pattern match with implicit AND between patterns, i.e. equivalent to running several greps in a sequence: grep pattern1 | grep pattern2 | ... So how to convert it to ...
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1answer
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sed special character replace not working in shell script

I want to write a script 'test.sh' that will take a user's input and replace all special characters with a '\' + the character. My script: #!/bin/bash echo 'input='"$1" arg=`echo "$1" | sed ...
0
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1answer
466 views

Remove a block of lines between two patterns [duplicate]

Possible Duplicate: Show only text between 2 matching pattern In a bash script using sed how can I remove a block of lines beginning with -pattern a- and ending with -pattern b- where the ...
1
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1answer
819 views

Using grep command and backreferencing

This is a pretty basic question, but I can't get my head around it. I'm learning Linux and one of the questions i've been given is; *The word sentimentalment includes the same three characters ...
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3answers
753 views

find with user variables

I am trying to call find with a few variables. So far I had this: DIRECTORY="./ " FILENAME=-regex" .*test.*" find $DIRECTORY $FILENAME Which works fine. If I change the filename to : ...
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4answers
634 views

Replace text between brackets

I'm using awk '{ gsub(/BAR|WIBBLE/, "FOO"); print }' to replace text in data like: SOMETHING [BAR, WIBBLE] SOMETHING [BAR] This gives the desired result of: SOMETHING [FOO, FOO] SOMETHING [FOO] ...
2
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2answers
473 views

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 ...
2
votes
3answers
2k views

remove white space before delimiter with sed

I have data of the following format that I want to input into LibreOffice calc data | num | num | num | num For some reason Libreoffice does not think the string "3214 " is a number by ...
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3answers
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Compacting `find` name patterns

I am using find . -name '*.[cCHh][cC]' -exec grep -nHr "$1" {} ';' find . -name '*.[cCHh]' -exec grep -nHr "$1" {} ';' to search for a string in all files ending with .c, .C, .h, .H, .cc and .CC ...
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2answers
213 views

Match a simple Regex

I need to match this: (tt\d{1,10}) in a file with the file ending txt. I have tried grep and ack-grep but without results. ack-grep -G \.txt$ -g "(tt\d{1,10})"
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4answers
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Change currency format to generic number using sed

I am working on a large csv file with all coma separated entries. The entire document is composed of plain numbers, except for a few columns reflecting currencies that are formatted as text. For ...
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6answers
489 views

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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4answers
3k views

AWK - how to reduce the greed of a regular expression?

I have an example: echo "@article{gjn2010jucs, Author = {Grzegorz J. Nalepa}, " | awk '{ sub(/@.*,/,""); print }' Is it possible to write a regular expression that selects the shorter pattern? ...
11
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3answers
2k views

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 ...
0
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1answer
799 views

Asking ls to only list files in a path that match a specific glob/regex

In Zsh: Is there a way to use ls to only list files and folders in the current directory that match a specific globbing or regex pattern? For example, say I have multiple files that start with the ...
2
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3answers
549 views

Find word in sentence with Bourne Shell (sh)

I'm trying to determine if a particular word appears in a sentence using Bourne Shell (sh). For example: #!/bin/bash INPUT='Lorem ipsum dolor sit amet.' if [[ "$INPUT" == *dolor* ]] then echo ...
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2answers
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Replace the shortest match of a string pattern

I have this string: update mytable set mycol=myvalue where mycol=yourvalue; I need to convert it to: insert into mytemp select * from mytable where mycol=youvalue; I can accomplish it like this ...
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1answer
675 views

Regular expression how to get value in shell script?

I have to write a shell script to get value from a string, something like: string="abcdef" pathName How can I use grep command with the use of regular expression to get "pathName"?
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3answers
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with sed, how can I replace word within a matching line?

I am trying to write a sed expression to detect lines similer to this: s0:12345:respawn:/sbin/agetty -8 -s 115200 ttyS0 linux and replace the "ttys0" with "something_else" I do not want to detect ...
4
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1answer
379 views

Emacs simple arithmetics in query replace

Is it possible to do the following in emacs: Query replace all numbers in a region by the number +n, for example if you have: 12 and 7 are nice numbers let n be 3, then it should transform to 15 ...
0
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1answer
144 views

awk extended pattern matching (embedding pattern matching in actions for already matched strings) [closed]

I want handle strings of the form: PREFIX_TYPE_N,DATA So, does the *awk (gawk, mawk, nawk) support including pattern matching in the action for already matched string? Something like this (of ...
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2answers
443 views

How to find and replace files contents that match a pattern?

Suppose we have a folder named Project. I would like find each file in the folder that contains the pattern &$ at the function call. For example should replace: AnyFunction(&$arg); with ...
2
votes
2answers
381 views

AWK match string, not Regex

How do I match a string with AWK? Say I have the string [(*.+ it should only match strings containing the string [(*.+. The string is entered by the user, so if you know a cli utility that can ...
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5answers
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(Mac Terminal) sed to parse JSON … what am I doing wrong?

In Mac Terminal, I'm trying to parse the "name" out of this JSON response: {"created_at":"2012-08-27T20:04:27Z","deleted_at":null,"id":21462840,"item_type":"video","name":"CastingBy-v12 ...
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What is the definition of a regular expression?

I recently got into a friendly argument with Ghoti about what constitutes a regular expression in the comments to my answer to this question. I claimed that the following is a regular expression: ...
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4answers
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How can I find all files in a folder that contain a match of a regular expression in the file name?

I'd like to find all of the files in my home folder on Linux (Ubuntu, in this case) that contain a match a particular regular expression. Is there a simple Unix command that I can use in order to do ...
4
votes
1answer
133 views

Using Regex in vim movment

Is there any way to use regular expression for movement in vim. For example, I want to move my cursor to the first occurrence of the pattern abc. So can I do something analogous to fa but now a ...
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4answers
633 views

Sort input file by the results of a regex

I'd like to sort a file based on the results of a regex expression. For example, if I have the following property declarations in Obj-C @property (nonatomic, strong) id <AlbumArtDelegate, ...
4
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2answers
397 views

Find and regex

What am I doing wrong with this find expression? ; touch ook ooks ; find . -name 'ook' -or -name 'ooks' -type f ./ook ./ooks ; find . -name 'ook[s]?' -type f [returns nothing] ; echo $? 0
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4answers
539 views

Stripping all vowels but the first from a set of strings

I have a string comprised of multiple substrings, separated by underscores. For example: AbcdAEfd_hEgdgE_AbAAAAA. I need to remove all vowels except the first from each substring. So: AbcdAEfd -> ...
3
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2answers
274 views

Do procmail recipes have an alternator “or” operator?

Given the following procmail recipe: :0: * ^Subject:.*viagra.* * ^From:.*viagra.* /dev/null Procmail would only delete emails that were both from viagra, and had viagra in the subject. Is it ...
2
votes
1answer
184 views

prepend digit to filenames which begin with digits (with zmv, please)

I have a directory with files named like 19.png, 20.jpeg, and README00.txt I want to rename these to 119.png, 120.jpeg, and README00.txt. I would like to do this with zmv as it works well in so many ...
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1answer
54 views

cclive: what kind of regexes are allowed?

Is there a place where I can look, what kind of regexes I can use with the --tr option from cclive?
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votes
3answers
337 views

VIM see regular expressions matches as you type

If I type /regex then the cursor temporarily jumps to the first match and all matches are highlighted. This updates as I type. Is it possible to get this behavior when I'm getting ready to make a ...
2
votes
1answer
318 views

How to join vCards lines

vCard uses a special way to split long lines: At 75 characters, insert a DOS newline and a space. Joining therefore means to replace all occurrences of the sequence "CR, LF, space" with an empty ...
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votes
2answers
1k views

Sort by regular expressions

I've got a set of POSIX regular expressions* ^BEGIN:VCARD\r$ ^VERSION[^A-Z] ^FN[^A-Z] ^N[^A-Z] ^NICKNAME[^A-Z] ^EMAIL[^A-Z] ^X-\([A-Z-]*\) ^TEL[^A-Z] ^ADR[^A-Z] ^ORG[^A-Z] ^TITLE[^A-Z] ^BDAY[^A-Z] ...
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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 ...
2
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1answer
560 views

Emacs: query-replace, regular expression, reuse of search result

How do I combine something like query-replace with a regular expression search-and-replace that in part reuses the search result? In my case, how to transform The programmers are "sort of" ...
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2answers
208 views

Difference in regular expression handling between Perl, Kikki, and Kodos

#!/usr/bin/perl $mystring = "[2004/04/13] The date of this article."; if($mystring =~ m/(\d+)/) { print "The first number is $1."; } Perl returns 2004, but Kiki and Kodos return /04/. Why ...
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572 views

Weird zsh grep -P behaviour

I connect to server with PuTTY from Windows. I have a long yet not touched (I suppose) by hands of local admin config: $ cat /opt/jira/.subversion/config ... ### must be enabled, which is ...
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5answers
851 views

How to remove the (1) from filenames using the find command

I recently converted all of my FLAC files to a lower sampling rate of 44.1 kHz and bit depth of 24 bits (because iPhone/iPod don't support anything above that) using XLD on my Mac OS 10.7 (Lion). ...
0
votes
1answer
115 views

Replacement in VIM with regular expression matched part unchanged

Suppose I want to append two digit numbers in my file with "some_thing". Like from this: 12 23 45 to 12_something 23_something 45_something How can I do this using regular expression ...
2
votes
2answers
367 views

Detect pattern repetition in a file

I want to make sure a file follows the following pattern: ... ... ... foo ... foo_KO ... ... ... bar ... ... ... ... bar_KO ... The file is extremely long, so, in other words, I want to make sure ...