grep is a command-line tool for searching text patterns in files

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How to get the lines that contain -R with grep

How can I find "-R" in files with grep? I tried grep "-R" *.GNU to get the lines that contain -R, but it returns nothing.
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2answers
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How to search for a string only in textfiles? (recursively)

I can list all the textfiles (by mimetype) in a folder with: find . -type f -print0 | xargs -0 file -i | fgrep -i text | sed 's/:$//g' 2>/dev/null | awk 'BEGIN {FS=": "} {print $1}' Ok. But how ...
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3answers
971 views

A problem with find and grep

I have defined the following alias in ~/.bashrc: alias fg='find . -name $1 | xargs grep --color $2' in order to write fg "*.txt" " my_text " and find all file that have extension .txt and ...
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3answers
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Regular Expression for finding double characters in Bash

I am looking for a regular expression that finds all occurences of double characters in a text, a listing, etc. on the command line (Bash). Main Question: Is there a simple way to look for sequences ...
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2answers
610 views

“Ungrep” - which patterns aren't matched

I'm looking for a command or script to do the following - given: file1.txt: abcd efgh ijkl mnop file2.txt: 123abcd123 123efgh123 123mnop123 I want a command that does something like this: ...
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1answer
129 views

questions on find and grep

With respect to the following find command-line find . -type f -exec grep -l strings {} \; I do not understand the usage of -exec and {} \.
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2answers
824 views

Get 'less' to display filename

Something that seemed quite useful to me when looking for a certain var in a bunch of config files: less * | grep some_var So this returns the value of some_var without manually looking through all ...
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2answers
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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 ...
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3answers
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How to specify characters using hexadecimal codes in `grep`?

I am using following command to grep character set range for hexadecimal code 0900 (instead of अ) to 097F (instead of व). How I can use hexadecimal code in place of अ and व? bzcat archive.bz2 | grep ...
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1answer
122 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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2answers
738 views

How to adjust column width in Linux command output

When I used this command on Red Hat Linux /usr/sbin/ss -i I get the following output below: State Recv-Q Send-Q Local Address:Port ...
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vote
3answers
872 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. ...
5
votes
1answer
136 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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2answers
994 views

grep - why do brackets in grep pattern remove the grep process from ps results?

Why do brackets in a grep pattern remove the grep process from ps results? $ ps -ef | grep XXXX [...] XXXX [...] grep XXXX $ ps -ef | grep [X]XXX [...] XXXX
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2answers
2k views

Grep to search directories for patterns inside a text file

I have a file where it contains a list of search patterns (searchPattern.txt). Its contents is similar to the contents below where there are 3000+ of them. 123456 234567 345678 . . . What I wanted ...
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4answers
289 views

Grep of many keywords over many files: speeding it up

I am currently facing a "performance problem" while using grep. I am trying to locate the occurrences of many (10,000+) keywords in many (think Linux kernel repository size) files. The objective is to ...
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1answer
59 views

How to get all Users and echo if they work or not?

How do I get a list of users(given from the command line) with grep and output if they are logged/work or not ?
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1answer
229 views

How to Get FreeBSD Grep to recognize '-' option?

I am using FreeBSD grep, version 2.5.1, and want to be able to have grep read the pattern from stdin. Other versions of grep I have used allow for the specification of - to enable this feature. ...
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5answers
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How can I recursively search directories for a pattern and just print out file names and line numbers

Currently I am using grep as follows: grep -lr <PATTERN> . This gives me the following output, containing a list of all files whose contents (not name) contain : ./path/to/file1 ...
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3answers
132 views

| Grep, Find which file the strings came from

I have a set of PDFs, and I am running strings * | grep message This returns the strings containing that method, is there anyway I can get grep to tell me which file it is from?
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votes
2answers
467 views

Search class names in jars

I'm using this command to search *.jar files for java classes, and I only get the name of the jars that contain those classes: grep -ral --include=*.jar SignonEJB . How can I also get the class ...
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4answers
6k views

Number of files containing a given string

How can I count the number of files (in a directory) containing a given string as input in bash/sh?
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2answers
962 views

Tail -f piped through grep not outputing to file, but outputs to console

I'm using the following command tail -f /mydir/myfile | grep "searchterm" >> outfile Without the -f it works fine, but with the -f, which I need, nothing is written to the file. The ...
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2answers
771 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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votes
1answer
5k views

How do I redirect output from the find command (that uses grep) to a log file?

Consider the code to search for all files containing the pattern "search string": bash-3.2$ # The below find works fine.. bash-3.2$ find . -type f -exec grep -il "search string" {} \; bash-3.2$ # But ...
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3answers
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shell script to read from multiple files in parallel

I need to write a script that runs parallel and looks for a string in multiple files. I tried a lot of options but they slow down the speed of my processor.
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xargs grep suggestion

grep -v "\<Swap" instruments.log | awk '{ idx=index($0, "MasterId="); masterId=substr($0, idx+length("MasterId=")+1); masterId=substr(masterId,1,index(masterId,"L")-3); print masterId; }' | xargs ...
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1answer
1k views

How can I keep color codes with grep input?

It I grep something twice: ... | grep foo | grep bar It seems foo is not highlighted. Infact, it seems grep removes colorcodes from its input; Any way to prevent this?
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3answers
505 views

Help with a find command

I have a bunch of directories. Inside these directories is a cover letter and a zip archive of work. I wanted to run a quick and easy query to open up all the cover letters so I can decide if it's ...
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2answers
192 views

Split using sed

I have to split [X] ||| you owns the [X,1] ||| you own the [X,1] ||| 1 0.02020 0.07847 0.36788 3 -0.00000 -0.00000 at the pipes and output those line whose 2nd and 3rd argument are different.
3
votes
1answer
245 views

Understanding grep --label=

I am looking for an explanation how grep --label=LABEL works: Maybe somebody can give me an example [or two] on what --label= is for. I understand what grep and zgrep are supposed to do – the ...
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2answers
1k 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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3answers
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What is the difference between grep -e and grep -E option?

I am trying to understand the difference between grep -e and grep -E. Now from grep manpage I got: -E, --extended-regexp Interpret PATTERN as an extended regular expression (see below). ...
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2answers
311 views

Fast utility that indexes files/directories on centos 6 for faster searching through the filesystem

I need to often search a large directory structure (with 1 G / 13K files of data). find / grep take a lot of time. Is there any utility (or can one make an index of these files) for faster searching.
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3answers
648 views

Very strange behavior with grep and IFS

I'm having trouble using grep, the returned results are "n-empty", I mean without the 'n' character... This is the script sample : OLDIFS=$IFS IFS="\\n" i=$(grep -ril $1 *) echo $i IFS=$OLDIFS ...
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2answers
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Can grep return true/false or are there alternative methods

I'm trying to write this script for an assignment - it's only the second one I've written so bear with me. As a part of this script, I need to be able to check if the first argument given matches ...
5
votes
3answers
6k views

Search for values in 2 columns from CSV

I have a csv files with say 20 odd columns. I need to get the 14th and 15th column values where value in 14th column is say "VALUE1" and value in 15th column is "VALUE2". My condition gets satisfied ...
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2answers
286 views

Search and replace full line in recursive files

I'm using: grep -n -H -o -R -e textword . List all file recursively under directory '.' with string 'textword' and show the file, line and only portion matching. I need to remove lines that ...
5
votes
3answers
441 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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votes
2answers
149 views

Can I make grep treat escaped multiline as a single line?

How can I make tools like grep treat multilines escaped with a backslash as a long single line? Let's say I have some files that looks like this: testvar=test1 \ test2 \ test3 ...
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votes
6answers
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Is there any alternative to grep's -A -B -C switches (to print few lines before and after )?

grep -A 2 -B 3 prints 2 lines after the grep string and prints 3 lines before. grep -C 3 prints 3 Lines before and 3 lines after Unfortunately, the grep I'm using does not support these ...
4
votes
4answers
3k views

cut / grep and df -h

How can I grep or cut the "173G" under "Verf"? I need this for Unix scripting in school. jonas@jonaspc:~/$ df -h /dev/sda2 Dateisystem Größe Benutzt Verf. Verw% Eingehängt auf /dev/sda2 ...
4
votes
3answers
1k views

Uniquely identifying java processes with same name

I have two java processes which run using the same file name, MyApp.jar (for example). /usr/java/latest/bin/java -jar MyApp.jar These jars exist in different places and use different ...
3
votes
1answer
551 views

Output of `java -version` not matched by grep or awk

On my Linux machine, it isn't clear to me why if I do the following then I don't get only the version string ("1.5.0_32"). # java -version | grep version | awk '{print $NF}' java version "1.5.0_32" ...
0
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1answer
93 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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3answers
581 views

Newbie struggles with grep, sed, awk to filter html

I am a beginner linux user, trying to teach myself how to use linux tools on a cygwin install. I decided to make up a project to try to teach myself the basics of shell scripting and simultaneously ...
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5answers
1k views

How to find files with 100% NUL characters in their contents?

What is the Linux command-line command that can identify such files? AFAIK the find command (or grep) can only match a specific string inside the text file. But I want to match whole contents, i.e. ...
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votes
2answers
320 views

add “#” in begining to selected lines in File

Requirement : ADD someting (i.e #) in begining of every line in file A which is grep from file B File A abcd abdc sdfg asdfa jon ram File B jon abcd grep file B from file A and add "#" ...
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votes
1answer
95 views

How can I get grep to work with “->” as the pattern?

I have this text in a file called temp: -rw-r--r-- 1 root root 15776 Oct 15 2010 dnd-copy -rw-r--r-- 1 root root 15776 Oct 15 2010 dnd-link -rw-r--r-- 1 root root 15776 Oct 15 2010 dnd-move ...
4
votes
5answers
9k views

make grep output without trailing newline

Please consider this snippet: X=$(grep -m1 'some-pattern' some-file | sed -n 's/.* //p') I want to put last word in a variable if some pattern condition is matched for lines in arbitrary text file ...