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

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3
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2answers
22 views

Simple significant usage of '/M' multi-line address suffix?

For GNU sed v4.2.2-7, info sed says: '/REGEXP/M' '\%REGEXP%M' The 'M' modifier to regular-expression matching is a GNU 'sed' extension which directs GNU 'sed' to match the regular ...
5
votes
5answers
109 views

Non-greedy match with SED regex (emulate perl's .*?)

I want to use sed to replace anything in a string between the first AB and the first occurrence of AC (inclusive) with XXX. For example, I have this string (this string is for a test only): ...
176
votes
6answers
382k views

How do I grep for multiple patterns?

I want to find all lines in several files that match one of two patterns. I tried to find the patterns I'm looking for by typing grep (foo|bar) *.txt but the shell interprets the | as a pipe and ...
6
votes
1answer
147 views

file(1) and magic(5) : prioritizing a result

My question follows that one: file(1) and magic(5) : describing other formats . I want to describe a FASTA sequence ( http://en.wikipedia.org/wiki/FASTA_format) It could be a DNA sequence (with only ...
-3
votes
0answers
19 views

Print lines in one file matching patterns in another file [duplicate]

There are some phone numbers in one file I need to grep information from other file using that numbers among larger set of numbers and their information and result should be placed in separate file ...
1
vote
1answer
20 views

is there a way to use regexp with aptitude?

I use an alias to find new packages whenever I update the package index. [$] alias aptn aptn='aptitude search '\''~N'\' Now while this works, I also get a bunch of -dbgsym packages which come ...
30
votes
3answers
37k 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 ...
1
vote
2answers
39 views

Returning the output from Perl Regex

I've been trying to just return the inet values from UP adapters in ip addr, 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1 link/loopback 00:00:00:...
2
votes
2answers
189 views

Renaming using terminal and regexp to remove leading numbers from filenames

I want the following files to be renamed removing the sequence numbers. 01 X.mp3 to X.mp3 02 Add Me In.mp3 to Add Me In.mp3 I am trying with the below rename command. rename -v -n 's/^\d+\s*([a-z]+...
4
votes
1answer
73 views

Exploit in bash script parameter possible?

I want to pass an e-mail address from a web form to a bash script. I'm using the following regex: /[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,4}/ Is this sufficient? Or could one embed an exploit?...
2
votes
1answer
54 views

Can't do substitution in a sed program

Q. I want to write a 2 line program that lets me substitute "the" with "zee" and "The" with "Zee". Here is what I'm doing: I'm writing a sed program for example, program.sed. Inside it, I'm ...
4
votes
1answer
446 views

Sed command that would ignore any commented match

I'm trying to create a sed command using regex in order to substitute something in a text file only if it is not commented but I'm running into some troubles due to my almost non-existent knowledge of ...
1
vote
1answer
26 views

Bash Built-in Regular Expression Usage

I've tried to find all line's which begin with at least 1 tab. Several Variations didn't work out. The most Basic one: #!/bin/bash FILE=emptiness { while IFS=""; read line do regex='^[\t]+' if [[ $...
6
votes
5answers
11k views

Remove backslashes from a text file

I have Input: NISHA =\455 Output: NISHA = 455 I want to remove \ from output. I tried to use command sed "s/[\]//g" P but it is not working and it flags an error: character found ...
1
vote
1answer
41 views

extract servers' blocks from Nginx conf

I have the following conf file for nginx: user www www; ## Default: nobody ... events { worker_connections 4096; ## Default: 1024 } http { include conf/mime.types; ... server { ...
3
votes
1answer
130 views

Match RH[A-ZA-Z] with grep

How can I match with grep the regex RH[A-ZA-Z], so string includes RH with two characters that both are a letter between A and Z? I tried this but without success: yum list-security --security | ...
0
votes
0answers
47 views

Regular expression in expect command

I need to match a string and a newline with a regular expression or something like split when using the expect command on Linux. Here is the example of the command output: Notification value: 34 39 ...
1
vote
2answers
5k views

Pages don't get blocked with Squid over HTTPS

I have set up Squid to block pages on my own system (i.e not on a network), and I'm trying to get SSL to work with page blocking. To this end, I've set up ssl-bump and installed the certificate to my ...
0
votes
2answers
28 views

How to delete the slash using REGEX

Hello I am trying to delete the /. I have problem looks like this , find all the files with the .sh extension in the current folder and delete the ./ before the name and the .sh after the name and ...
2
votes
2answers
44 views

sed to print pattern that spans across lines

I'm learning sed and I'm currently stuck with the following problem: I want to extract the lines found between ^C's from the following output: banner exec ^C This is the banner ^C banner motd ^C ...
6
votes
4answers
1k views

How to add a header and/or footer to a sed or awk stream?

I have a bunch of output going through sed and awk. How can I prefix the output with START and suffix the answer with END? For example, if I have All this code on all these lines and all these ...
1
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1answer
36 views

Regular Expression ^$ not working on UNIX using grep command

I'm facing a problem in using the regular expression ^$ on UNIX. When I type grep '^hello$' text on the command line, as a result it should match the "hello" word because it is the only word on a ...
-1
votes
2answers
34 views

Find first unique occurance of match in file using regex

I would like to find the first unique occurrence of a match within a file. In the example data below, I would like to find the first occurrence of each Chunk Chunk 1 some text second line of random ...
-1
votes
0answers
66 views

sed replace or add variables into file

I'd like to use the following function (which is working for me): if grep -q HOSTNAME=noob hostname.ini; then sed -i "s/HOSTNAME=noob/HOSTNAME=pro/g" hostname.ini; else echo "...
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0answers
24 views

convert attachments of type winmail.dat (TNEF) to “real” attachments in stored email messages, recursively in MailDir

Some email messages contain the attachments in a format called TNEF (Transport_Neutral_Encapsulation_Format). This attachment is usually called winmail.dat. Extraction tools exist for linux, but ...
4
votes
1answer
44 views

How do I search bash's history in vi mode for “foo.*bar”

I have my bash environment in vi mode (set -o vi). So I can type <ESC>/ followed by a word, followed by enter, and bash searches for the word in the history. Since / is also vi's method to ...
3
votes
2answers
158 views

`cut`: selecting columns containing a string

I have a big file with several columns on each line. I'm familiar with using cut -f -d to select specific columns by their number. I checked the manual for cut and it doesn't seem that there's a way ...
1
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2answers
38 views

using gsub in awk to replace a word with parentheses

Hi how can I use gsub to replace a word which has parentheses. Here I want to replace ABC(T) with ABC/G awk ' {gsub("ABC\(T\)","ABC/G")}; Print $0' "$FILENAME" > tmp.tmp && mv tmp.tmp "$...
0
votes
3answers
65 views

Vim Search and Replace - Regex

I want to perform a search and replace. A newline before any non-digit should be replaced with tab. I tried %s/\n\D/\t/g but it replaced the first character of the word following the newline, which ...
0
votes
1answer
35 views

pattern regex for apache rewrite

I have a bunch of URLs counting to thousands i need to redirect and there are thre main patterns in URL first pattern There is a dash - starting the title url and want to remove that dash e..g www....
3
votes
2answers
61 views

magic example using search and/or regex

I am trying to have the file command detect some Windows text files that were never meant to be classified by file... The best choice seems to use regex to match the line content, but I cannot find a ...
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5answers
71 views

How can I use the rename command to fix these file names?

I'm trying to change files that look like 01 Track name.mp3 into 01 - Track name.mp3 So far my futile attempts were rename '0. ' '$&- ' *.mp3 rename 's/0. /$&- /' *.mp3 rename '/0. /' '/$&...
0
votes
3answers
79 views

Find-grep for List of .tex Files?

My document.tex where I want to get the list of files, and grep those files with the term gastric \subimport{}{1.2_protocal_answers.tex} \subimport{}{2_protocol_answers.tex} 1.2_protocal_answers....
1
vote
1answer
348 views

Easy Regex on Apache Logs

I'm struggling to create a regex for Apache logs. It's for ignoreregex on Fail2ban. I'd really like to be able to put something like /house to catch all files in that directory or /house/jonross....
0
votes
0answers
30 views

shell scripting using sed

I want to compare specific string surrounded by alphanumeric and some special chars in file. For example: 5efa4083-7157-437a-ab9a-652ced2fc2ea;: AAA :;5efa4083-7157-437a-ab9a-652ced2fc2ea;BBB I ...
0
votes
1answer
27 views

Cannot find the right regex for rename

I have some TV shows stored on my Ubuntu server and I could rename them all, so Kodi can recognise them, exept one: First Episode, first Season: Name - S01E001 - Title part1 Name - S01E001 - Title ...
2
votes
1answer
45 views

How can i replace multi line string using sed? [closed]

I have tried the following command:- [root@10 bin]# cat temp asdjahskjdhajksdhjkashjahfksjdhfkjsddhflkdsjhfklsdajhfklajshdkjalsdlkjasdhkljas hskdajkdhkjas cast $recv $UE_CAPABILITY_ENQUIRY ...
8
votes
3answers
8k views

Regex alternation/or operator (foo|bar) in GNU or BSD Sed

I cannot seem to make it work. GNU sed documentation says to escape the pipe, but that doesn't work, nor does using a straight pipe without the escape. Adding parens makes no difference. $ echo '...
1
vote
3answers
65 views

grep on interactive program

I have an interactive shell-like program, that outputs a lot of irrelevant error messages, that confuse our customers. Each of these error messages are full-line messages starting with "%". So the ...
1
vote
2answers
46 views

sed: Grabbing and replacing all data between last backslash and a comma

I have data in a csv format that looks like this: F1309-042543,07/14/09 01:39:25,N/A,C:\windows\system32\netsh.exe,N/A,True F1309-042543,11/21/10 03:24:02,N/A,C:\Windows\System32\networkexplorer.dll,...
0
votes
3answers
36 views

Escaping regex sed (1 lowercase, 1 uppercase, 1 symbol, 1 number) for bash

The goal is to remove every line not containing one uppercase, one lowercase, one special character and one number from a file. I am unable to run this regex: (?=.*?[A-Z])(?=.*?[a-z])(?=.*?[0-9])(?=....
3
votes
3answers
247 views

Use sed with back references

I am trying to remove a space between 2 strings, they are like this: 312.2 MB 123.34 KB 487.1 GB I want to change them to: 312.2MB 123.34KB 487.1GB I've been trying and I can get: echo "312.2 ...
2
votes
4answers
250 views

How to match “4.4” from `uname -r`?

Pseudocode [ `uname -r` =~ ^4\.4.*$ ] && echo "yes" which is, however, unsuccessful in all cases. The uname -r command gives things like 4.6.0-040600-generic as an output.
6
votes
4answers
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How to use regex with AWK for string replacement?

Suppose there is some text from a file: (bookmarks ("Chapter 1 Introduction 1" "#1" ("1.1 Problem Statement and Basic Definitions 23" "#2") ("Exercises 31" "#30") ("Notes and References 42" "#34")) ) ...
0
votes
1answer
43 views

Regex in case statement [duplicate]

I'm having a hard time getting regex matches to work in a bash case statement. Example code: #!/bin/bash str=' word1 word2' echo "With grep:" echo "$str" |grep '^\s*\&...
0
votes
2answers
40 views

Add time from all log files using bash

I want to extract time from all of my .log files and add all of these times into a single entity. My log files are placed in nested directories. Directory structure for my log files: |-- temp-system ...
0
votes
1answer
48 views

Using sed to extract text between two strings [duplicate]

I have to use the AdaBrowse Html generator to create a bunch of formatted files. Unfortunately, all of these files contain headers before each function or procedure that follow no consistent form of ...
1
vote
3answers
180 views

Use regex to check if particular directory has folders starting with specific word

I am writing a script that checks a certain directory for any sub-directories starting with a specific word. Here is my script thus far: #!/bin/bash function checkDirectory() { themeDirectory="/...
6
votes
1answer
88 views

Perl one liner to find words longer than 63 characters

I have a number of XML files containing sanskrit texts to be converted to tex. Latex has a maximum of 63 characters per word for its hyphenation to work, everything longer than that will not be ...
0
votes
3answers
64 views

Regex pattern to replace multiple values via sed

I have a script in which I need to parse the IP address of the localhost, and replace the 2nd octet with a different value, but the value being substituted depends on what the value currently is... ...