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

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How can I combine grep with file and extra regex

I have a file of strings in each line. For example: AAAAA BBBBB CCCCC etc I want to check each string one by one whether it exists in a series of files in a specific directory. I ...
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103 views

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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846 views

How to grep for pipe |

How can I grep for line containing pipe character | or for character >: files content: |this is test where is > this is none now what I need using grep command is grep -iE "<some ...
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3answers
182 views

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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4answers
754 views

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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2answers
111 views

Remove 2 and 3 newlines in a text file but not 1

I'm developing on a max osx 10.8 and have no preferences to which tool to use probably sed but it doesn't matter. Update after comment: The input file uses windows new lines if that's complicates ...
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1answer
113 views

Why is this line included in the `logcheck` report email?

In addition to the Debian provided rulesets, I have added a file /etc/logcheck/ignore.d.workstation/wpasupplicant.local (owner root:logcheck, mode 0644) to my newly installed logcheck setup. I have ...
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1answer
179 views

grep: display filename once, then display context with line numbers

Our source code has error codes scattered throughout. Finding them is easy with grep, but I'd like a bash function find_code that I can execute (eg. find_code ####) which will provide output along ...
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115 views

vim regex to search for lines containing string1 AND string2

How in vim/vi can I search for all lines that contain string1 and string2, where either string can appear anywhere on the line separated by whitespace and possibly other words? I would also like to ...
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3answers
83 views

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}}, ...
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1answer
152 views

Execute a command within 'sed'

I have a list of random memory addresses saved in a text file, and I need to sed them out, decode them, and save them back to my file. However, the decoding operation I'm trying to perform is handled ...
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195 views

Replace all occurences of \ except \N

I have a file like this: 1,2,subjects,\mat\hs,unix\,\Nato,\N,123,\N I want to replace all occurences of \ with #, except for \N, such that the output looks like this: ...
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3answers
125 views

mv files to a different path which is constructed via a regex replacement

I have a directory full of files stored in subdirectories according to their filename, i.e.: 20d1/d325/52d1/20d1d32552d1a95249e62662fbdf924dd72c4027.jpg ...
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2answers
96 views

Backreferencing with sed

I have a database containing a list of unsigned longs representing a bunch of memory addresses followed by an offset within two brackets (e.g. Mem[offset], 0x2322AD4[3]), and some other data. What I ...
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2answers
109 views

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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1answer
853 views

Forcing Bash to use Perl RegEx Engine

As you may already know, a lot of the features modern RegEx engines support (back referencing, lookaround assertions, etc.) are not supported by Bash RegEx engine. Following is a simple Bash script I ...
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1answer
73 views

What are the commands that you can use in the beginning of a sed command?

I initially learned to do sed search and replace like so: sed -e 's/<stuff>/<replacement>/' However I recently learned that these will do something different based on what command ...
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823 views

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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218 views

using simple regex quantifier expression in grep

Does anyone know why ls | xargs -n 1 basename | grep -E '[0-9]{1}' does not only show occurrences of a single digit between 0-9? For example if I have: touch 1 touch 22 touch 333 touch test_file ...
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282 views

How can I grep for this or that (2 things) in a file?

I have a file that has "then"'s and "there"'s. I can $ grep "then " x.x x and then some x and then some x and then some x and then some and I can $ grep "there " x.x If there is no blob none ...
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2answers
70 views

Grep and regex, Why does the following return only a specific portion?

Why in the following: echo this is a line. | grep -o -E "[a-z]+\." The result is line. and not this is a line.? There is no word boundary or any other restriction on the regex.
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1answer
99 views

How to negate a regex inside another regex

That is, given a POSIX regex X, what POSIX regex is the complementary of X? (in a more detailed way: how to get regex X' that matches all strings that are not matched by X, but doesn't match any ...
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100 views

Removing second colon

Trying to create a simple script that lists mass mailing by the queue number that appears in /var/log/maillog. I'm starting off with this: [root@ditirdlns01 ~]# lsMails(){ grep -i ...
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3answers
2k views

extract part of string using sed

ls lib/oracle-11.2.0.3.0.txt | sed 's/lib.\([oracle.*]\)\.txt/\1/' It is giving the whole string instead of just oracle part until .txt What am I doing wrong? I can do it using awk as follows, but, ...
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86 views

Use grep with or [duplicate]

How do I search in a textfile with grep for the occurrence of a word or another word? I want to filter the apache log file for all lines including "bot" or "spider" cat ...
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1k views

Extract substring using regular expression on a Unix file

I have file with below contents . /ABC/RTE/AD_900_VOP_123/OPP /ABC/RTE/TRE/AD_900_VOP_145/BBB /ABC/RTE/AN_900_VFP_124/FBF /ABC/RTE/HD_900_FOP_153/WEW /ABD/RDV/AD_900_VOP_123/OPP ...
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630 views

syntax of ls --hide= and ls --ignore=

ls --hide and ls --ignore provides the possibility leave out files defined through regular expressions set after the --ignore= part. The latter makes sure that this option isn't turned off via -a, -A. ...
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78 views

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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1answer
480 views

rsync exclude based on file size?

Is it possible to exclude files in rsync over a certain size (e.g. over 250 MB)? And what if I also want to exclude hidden files? How would I exclude all hidden files or directories (those that ...
5
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1answer
112 views

What is the meaning of this test expression []? [duplicate]

I've seen someone use command: ps -ef | grep [h]ttpd and Output is: apache 25125 31006 0 21:54 ? 00:00:00 /usr/sbin/httpd apache 26869 31006 0 22:04 ? 00:00:00 ...
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Using sed to find and replace complex string (preferrably with regex)

I have a file with the following contents: <username><![CDATA[name]]></username> <password><![CDATA[password]]></password> ...
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302 views

regex to match identifiers without double _

I want a regex to match identifiers consisting of letters, digits and _, without double underscores. My current attempt: ^(?!_)(?!.*?_$)[a-zA-Z][a-zA-Z0-9_]+$ Example: Abdfsdfsdf__ 1B2345_ ...
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1answer
73 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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1answer
39 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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2answers
1k views

rsync certain files, excluding the rest, ignoring .svn/ directory, recursively

I'm using rsync to copy some files from a share to another. Recursively, I need to: Delete files at destination that were removed from the origin Only sync php and js files Exclude every other file ...
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2answers
285 views

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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1answer
103 views

How to ask for specific parameters with grep?

I need to look in /usr/share/dict/words for a 5-letter word that starts with d or D, followed by a lowercase vowel, and ends with s. I have tried everything but to no avail.
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488 views

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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2k views

bash - reading user variable into bash script grep

I've tried every possible combination to get this bash script working. It's part of a larger script, and it basically prompts for a username (to check if it exists) and returns the appropriate ...
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3answers
650 views

Remove string from a particular field using awk/sed

I have a file (>80,000 lines) that looks likes this: chr1 GTF2GFF chromosome 1 249213345 . . . ID=chr1;Name=chr1 chr1 GTF2GFF gene 11874 14408 . + . ...
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3answers
316 views

difference between .* and * in regular Expression

I've a file named "test" that contains linux Unixlinux Linuxunix it's linux l...x now when i use grep '\<l.*x\>' , it matches : linux it's linux l...x but when i use grep '\<l*x\>' ...
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380 views

Trying to remove all ids from an HTML file with grep

I'm trying to remove all id=" "s from an .html file but I'm not sure where I am going wrong. I tried using regular expressions but all I am getting is the .html file rendering in my Ubuntu terminal. ...
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2answers
55 views

Trimming one part if equal to another part?

I use an e-mail quote attribution string like this: On dd mmm yyyy hh:mm +hhmm, from info@example.org (Example Dot Org): where info@example.org is the sender's e-mail address and Example Dot Org is ...
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1answer
72 views

(e)grep and atomic grouping [comprehension question]

I am trying to understand the correct use of »atomic grouping« a.k.a. »independent subexpressions« a.k.a. »non-backtracking subpattern« [this are the terms I found ...
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60 views

Comment the if statement and the matching endif keyword

In vim, I can find the matching if statement and prepend the appropriate comment symbol. (e.g. %s/.alarm./#\0/g), but then I am left with dangling endifs that I have to find manually. I could simplify ...
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770 views

what is “an invisible whitespace character that takes up space”

One can look up Unicode Characters with Regular Expressions. On Jan Goyvaerts website I found a RegExp whose meaning I don't understand : \p{Zs} or \p{Space_Separator}: a whitespace character that ...
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1answer
373 views

How to highlight the whole log-line in color with multitail

I'm trying to use multitail to tail logs with color highlights. I defined a custom color scheme in multitail.conf, something like this: colorscheme:my-color cs_re:red:^\[E cs_re:yellow:^\[W ...
3
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3answers
952 views

Delete XML node containing certain element

I want to remove all Placemarks from a KML file that contain the element <tessellate>. The following block should be wholly removed: <Placemark> ...
0
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1answer
156 views

Regex awk to Cisco Interface

I would like to know if have some Sed/Grep or Awk regex to parse Cisco interface section, with specific attribute, like bellow. Content of file.txt ! interface FastEthernet0/1 no ip unreachables ! ...
4
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2answers
972 views

greedy and lazy regular expressions (comprehension question)

I am teaching myself regular expressions, and I got stuck at »greedy« vs. »lazy« repeatings. What I found out so far is that »greedy« means that the RegExp ...