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

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Searching file for string surrounded by two other known string?

Question title may be kinda vague, but heres what im attempting to do. I have a html file locally on my server which is changing fairly regularly. It has multiple occurrences of: <p>Jumble of ...
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69 views

how to modify matches to a regular expression with sed or another tool?

I need to manipulate text that's in a file. I need to append a right parenthesis – ) – after every number that's preceded by a comma – , – e.g., ,4   ➜ ,4) ,15 ➜ ,15) I am struggling to find the ...
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49 views

Why is logcheck reporting successful Horde logins?

I'm running Ubuntu 14.04 LTS server and use logcheck to report log messages. I have the logcheck-database installed which contains a horde3 ignore file for the server: ^\w{3} [ :0-9]{11} ...
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128 views

Retrieving words before certain characters without having to use Perl

I have where clauses for SQL queries in text form, and I'd like to extract the column names from them. The clauses can contain conditions like col_1 = 'Spruce' and col_2 in ('Argentina', 'Cameroon'). ...
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some POSIX Bracket Expressions not working

For example when I'm trying to find and replace something using g/[:digit:]/s/1/2/g Vim showing error: Pattern not found: [:digit:], while the string contains digits. Following POSIX Bracket ...
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76 views

How can I use regex to extract the text following two conditions into a variable?

I'd like to extract a setting for a given host in the ssh_config file and put it into a variable. Host mysite HostName 123.1.1.1 User myuser Port 13245 GSSAPIAuthentication no ...
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107 views

How to nest global matches with sed?

If I do: sed 's/match/replace/g' I know that sed will substitute replace for every occurrence of match on a line. But what if...? echo "match <please dont match this?>" | sed ...
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Remove patterns from string using bash

I'm trying to remove some patterns from a file input string (parsing file line by line). Here is a sample string: 1: (10/17 12:49:31.175) - CONSTANT ID1 - CONSTANT ID2: RAW DATA OUT > ...
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Regex for contains at least one instance of STRINGA and no instances of STRINGB

What regex will match: contains at least one instance of "1221", and no instances of "7474" i.e. matches "7777 1221 4543" but does not match "7777 1221 7474 4543" I suspect I have to use negative ...
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281 views

Regex works in shell but not through Perl script

I'm having trouble executing a Perl script through the Unix shell using Perl's system command. I've had more complex regex commands I had to adjust accordingly to convert from Unix to Perl, and ...
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173 views

Why does the same sed regex (after grep) fail when run in a bash script vs bash command line?

Here's the script. It is successful when I run it from the BASH prompt, but not in the script. Any ideas? When I say "fails," I mean the sed regex doesn't match anything, so there is no replaced ...
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661 views

How to get the JSON STRING from the given string

I have a string given below. I just need to get the first accountHeader (bolded) JSON string, I tried everything.. It didn't work. Can you help me to get the data? <START ...
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Where can I find documentation on shell script syntax for using a regex within a variable construct?

I'm debugging a shell script (which I didn't write) that contains this loop: read line < "$pid_file" for p in $line ; do [ -z "${p//[0-9]/}" -a -d "/proc/$p" ] && pid="$pid $p" done ...
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206 views

Parsing csv with sed and perl one-liner?

I have a web server which stores configurations to PostgreSQL, and I plan to retrieve information from a certain table and then later parse it into csv format. PAYLOAD <?xml version="1.0" ...
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113 views

Help understanding an egrep expression

I stumbled across the following egrep expression: egrep '^([^aieou]*[aieou]){5,7}[^aieou]*$' /usr/share/dict/words on this page: http://matt.might.net/articles/sculpting-text The expression is ...
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468 views

Brace expression does not work in find regex

I have two folders, CA01 and CA02 under current folder, foo: foo -+ | +-CA01 | +-CA02 When I type find . -regex ".*CA[0-9]+" -exec echo {} + Or find . -regex ...
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Tell a regex expression to skip the beginning of a line before matching

If I had a string like 45mb ./aaaa/bbbb/cccc/dddd and I use a regex like [^\/]*\/ it will match 45mb ./aaaa/bbbb/cccc/ I only want it to match ./aaaa/bbbb/cccc/ but I can't figure out how to do ...
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45 views

Matching hexadecimals with gawk

I have a binary file with the following content (printed in hexadecimal): $ xxd -p virus.com 5669727573b440bb0100b90500ba0000cd21 I can match the first 5 letters (which are the alphanumeric string ...
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linux + match IP ADDRESS with 3 octets or with 4 octets

how to match IP address with 4 octets or with 3 octets in one command? target - match xxx.xxx.xxx or xxx.xxx.xxx.xxx ( syntax should fit for Linux and Solaris ) how to merge the following commands ...
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645 views

Recursively edit files based on parent directory's name

I'm facing an issue I'm not quite sure how to overcome. I have a large directory with hundreds of folders, all following the naming scheme "a_b_x", with x being a random word. In every one of these ...
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795 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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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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808 views

Multiply certain numbers in a text -file by certain constant

I want an alternative solution to this jQuery hack, tasting a bit reinventing the wheel -- look I am sure I could do this with some one-liner using basic *ix tools. Look much easier and ...
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218 views

What special characters does grep parse by default? [duplicate]

Possible Duplicate: In a regular expression, which characters need escaping? I know there is the -E flag which treats the "search term" as a regular expression. However, it seems that even ...
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333 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 ...
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what is the correct regexp for mysql filter in fail2ban?

I use the default filter file /etc/fail2ban/filter.d/mysqld-auth.conf for fail2ban service. But there are some errors in file /var/log/fail2ban.log as: Found a match for '150815 10:42:54 [Warning] ...
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LFTP exclude file extensions

I am trying to mirror directories with lftp but I don't want to download filetypes that are notoriously large like .mp4 and .swf. But I am having trouble with the regex - and seeming like the ...
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48 views

regex usage in exim filtering

I'm trying to create an exim filter to block spam messages containing " 85% OFF" in the subject line. That's a blank space, then any two digits, then the percent sign, a blank space and the ...
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Interpreting regex wildcards with grep [duplicate]

This is a really simple question, but even after reading about wildcards/regex, I can't seem to grasp entirely what the differences between these commands are: grep . test.txt this one will look ...
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63 views

How to do operation on individual matches in a full line

I have a Verilog line like this: if (i2_0&!(i2_1)) (posedge i0_0 => (o:1'b1))=(0, 0); How can I convert it to a line like: if (i2_0 == 1'b1 & i2_1 == 1'b0) (posedge i0_0 => (o:1'b1))=(0, 0); ...
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369 views

nginx location regex with proxypass

I am quite new to nginx so excuse me in advance if i am asking something obvious. What i am trying to do is to proxypass to another server a request that comes to my nginx server in the form of: ...
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Bourne shell: ignoring certain kinds of stdin

I have a program that is currently working, but I need to modify it to ignore some stdin that is not fitting for its correct function. Right now, to run the program: printf "1\n3\n5\n" | sh prog The ...
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What is SELinux's regex type?

I'm trying to locate all files on my system matching an SELinux file context (fcontext). These contexts are specified using some regex, and I'd like to use find -regex ... to the same effect. However, ...
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sed regex not working for hidden characters

I have a list that has for some reason got some non alphanumeric characters appended to the end. I would have thought it would be a simple case of running : sed 's/[^A-Za-z0-9]$//' To replace ...
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Take the unknown contents of variable as literal in sed [duplicate]

I have two files: a.patterns contains patterns in a one per line way "`" "^" "<" "<(" "<)" "<[" "=" ">" "_;|^+*+?@" and b.data contains comma separated values. 1,1,0,"*",1 ...
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grc: Highlight capture groups only?

Recently I came across grc and I find it really simple. However, I would like to highlight some chunks of regex-matched text. For example, svn status properties conflict highlight I hoped to work: ...
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100 views

Need .htaccess Rewrite Rule To Remove Trailing <br%20/>

I have links that for some reason have a trailing <br%20/> and I don't know where they are coming from to try and fix them. So I need a general rewrite rule to remove them so the links won't ...
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715 views

Aix grep wildcard not working

I have a file called message that has the line CSC/UT/USA/WBIMB/SAP/orders05:orders05/ORDERS05/NONE/ORDRSP/758 I am doing a grep (Platform is AIX 6.1) grep ...
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Regexp on data flow

I want to test if in my data flow, there is something, and do an exit code. I use gammu monitor, which provides a data flow, for example : [root@MYSERVER ~]# gammu monitor Press Ctrl+C to break... ...
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Grep and sort several unsorted things in several lines (in one document)

I have a file with several unsorted things in one line which I want to put into a new file This is an example of part of the file I have: X1314448: SaMi|SM_g2554.t1 SaMi|SM_g5072.t1 Des|Des_g3808.t1 ...
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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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859 views

Ignore lines containing a capital letter

Why does the following command still return some lines containing a capital letter? aspell dump master | grep ozz | grep -v '[^A-Z]'
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763 views

How to delete html tags from a file using sed ?

I have a file that is mixed with both normal text I need and html-tags. I know that with REGEX it is possible to recognize html tags and with sed one can swap those for an empty string, but I do not ...
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bash event not found trying to match and exclude parenthesis in grep

In a very long line I'll summarize with: (foo),(bar,baz(word,right),(end) I want to print only: (bar,baz(word,right To match the second parenthesis, I exclude the word that follows the ...
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What does ^> mean in a grep pattern?

What does this command do? grep "<[^>]*>" inuux.xml What is searching for?
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AWK print regex pattern

I am trying to print a regex pattern for the following piece of mail log. In particular I am trying to get the ID between the square brackets (see the second line for reference). Mar 29 03:48:13 ...
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How to extract the similarities between two strings

I have two strings in two different sentences: string 1: 30 mutation alanine for valine string 2: alanine at position 30 is there away to find the similarities between them as it is clear they ...
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grep for lines/files that contain exactly X chars

Here's the output of a grep command I ran: [user@localhost] : ~/Documents/challenge $ grep -i -e ".\{32\}" fileA fileB fileA:W0mMhUcRRnG8dcghE4qvk3JA9lGt8nDl fileB:observacion = new Observacion(); ...
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To remove \n but not \n\n

Data 23. Lorem A) he B) ha C) hu c 2. Ipsun yes right to write something here? A) Ok B) No C) yes b 292. Ipsun A) Apex B) hello b 289. He A) hu B) Ha C) He The right answer is: 1) Ab 2) Abc 3) ...
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Bash Combine Replacement and Sub String Extraction in One Step

For a string in this format: ./my-site.sub.domain.com I would like to remove the .,-, and /, and trim the remainder to 16 characters: mysitesubdomainc I've done this ...