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

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4
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4answers
161 views

extract lines according to a particular column

I have a CSV file like CK,ck XYZ,xyz,xyzs ABC,abc,abcs PQR,pqr,pqrs LMN,lmn, IJK,ijk, I have to check if something is written in column 3 except whitespace, then display the whole line.the output ...
4
votes
4answers
54 views

regexp which matches all tokens independent of order

I have a quick (and hopefully simple) question about regexps. I'm trying to think of a regexp which matches all of a set of tokens irrespective of order. So for example I have a file with the names ...
0
votes
1answer
33 views

Improve execution time for recursive md5sum check?

This recursive md5sum check for 40000 items of 11.8 GB takes 2 minutes: ret=$(find "${target}"/ -name ".md5sum" -size +0 | while read aFile; do cd "${aFile%/*}"; md5sum -c ".md5sum"; done | grep -v ...
1
vote
1answer
50 views

ls and find command excluding a certain directory

I want to do this: ls -altrhS 'find / -type d \( ! -name tmp -prune \) -size +10000k 2> /dev/null -print' | egrep -v 'ibd|MYD|MYI' So I want to list, in that format, files of a specific size ...
0
votes
1answer
256 views

Grep a string with spaces from a file

#!/bin/bash LIST=/errors_exception.txt cd /test for PATTERN in `cat $LIST` do for FILE in $(ls) do if zcat $FILE | grep -Fxq "$PATTERN"; then echo "$PATTERN found ...
3
votes
3answers
241 views

Get the part of a line before the last slash

I'm trying to write a conky script that shows my MPD album art, a 'folder.jpg' in the album folder. My current plan is to use mpc -f %file%, which prints out the file name and path, and then cut out ...
5
votes
7answers
677 views

How to find a position of a character using grep?

I need to identify the postion of a character in string using grep command. Example, the string is RAMSITALSKHMAN|1223333. grep -n '[^a-zA-Z0-9\$\~\%\#\^]' How do I find the position of | in the ...
-1
votes
2answers
39 views

Searching out a pattern from Logs

The format of the logs is in this manner: Junk Junk Junk : Junk Junk Junk:IP/Port Junk Junk I want to search using the IP and the output should be only the IP/Port part of each line in that log ...
2
votes
4answers
274 views

Only cat from specific line X (with a pattern) to other specific line Y (with a pattern)

A little extended problem from "cat line x to line y on a huge file": I have a huge file (2-3 GB). I'd like to cat/print only from the line having "foo:" to the line having "goo:". Assume that "foo:" ...
5
votes
4answers
549 views

How to add a carriage return before every newline?

I have a file that only uses \n for new lines, but I need it to have \r\n for each new line. How can I do this? For example, I solved it in Vim using :%s/\n/\r\n/g, but I would like to use a script ...
2
votes
2answers
34 views

Live replacement, while viewing log using LESS

It's very convenient to monitor logs using less command - you see what is going with your system as it happening. The bad thing is that my logs are optimized for grep tool: each atomic action is ...
0
votes
1answer
21 views

find file read it and search for specific identifier

I'm trying to find out in what files some specific identifiers are being used. I know the file's name and know the identifier, therefore I use the following command to achieve my desired result: find ...
2
votes
5answers
286 views

Remove multiple lines after a pattern match but only after pattern match

I am trying to remove all instances of a pattern match from a file if it matches a pattern. If there is a match, the (complete) line with the matching pattern and the next line get removed. The next ...
1
vote
2answers
64 views

grep contents of files based on a list of files

Running CentOS 6.5, qemu-kvm. I have a script which builds a list of running VM's. I want to pull information from those .xml files of only the VM's that are running. cat /dev/null > ...
8
votes
7answers
381 views

How can I “merge” patterns in a single line?

I am doing grep and sed and I get 2 lines of a file that I am interested in. How can I get these lines in a single line ending with the new line character? Now I am getting: pattern1 pattern2 ...
0
votes
2answers
40 views

grep command. '^1' won't work

ttys000 -bash: cat n_modified.txt 1 calibre library 2 desktop 3 documents 4 downloads 5 library 6 movies 7 music 8 pictures 9 public 10 ...
0
votes
0answers
29 views

How to get ids from xml file into mysql?

I've got 8 xml files and need to do some work on these records in mysql. What is a good way to get these IDs into mysql? <?xml version="1.0" encoding="utf-8"?> <Records> <Record> ...
2
votes
1answer
43 views

Grep does not seem to work properly for me

Command: LC_ALL=C fgrep -f /root/inputfile.txt *.txt > outputfile.txt inputfile contains this kind of stuff; -name1: -name2: -othername: *.txt (multiple files) contains things such as ...
3
votes
4answers
102 views

How to remove text matching specific patterns from a file

I want to compare two files to check for differences between them, fileA and fileB. fileA is like a template file and fileB is the file which I want to compare to it. Anytime I find a difference I ...
2
votes
1answer
31 views

Get each column which contains multiple spaces?

My file: subnet 172.25.10.0 netmask 255.255.255.0 { option domain-name-servers 172.25.10.9, 8.8.8.8; default-lease-time 300; max-lease-time 7500; range dynamic-bootp 172.25.10.10 172.25.10.30 ; ...
0
votes
1answer
40 views

Quote escaping struggle with grep and sed

I'm writing a bash script to extract data from html tags and I found this command in another thread : grep -o '<tr>.*</tr>' HTMLFILE | sed 's/\(<tr>\|<\/tr>\)//g' > NEWFILE, ...
-4
votes
1answer
95 views

What command in bash to search for this string?

file.txt contains: aa=testing sss=whoiam bbb=findme What command do I use to search for testing and print it? Expected result: # you search testing
4
votes
1answer
72 views

unexpected output with grep

I am using pyrit. For those who dont know, pyrit allows among other things to check if a wpa handshake key is valid: pyrit -r file0.cap analyze when a file does not contain a valid key, here is ...
3
votes
2answers
106 views

Getting the combined count of all occurences of a string under multiple directories?

I have a (hopefully) interesting problem that I could use some advice on. I have a system that's essentially used for storing logs. It has a directory structure like: YYYY/MM/DD/hostname/ There are ...
4
votes
6answers
183 views

grep with a lot of files which contains a lot of lines?

Imagine we have a lot of huge(30000 line)files: a.2014-05-06, a.2014-05-07, a.2014-05-08 and so on. I know that we can grep a line with word using this command: grep "word" a.* First I guess this ...
0
votes
0answers
29 views

Get only files specified in egrep

I could to like ask how to get only the files that contains or match with this command [ "$(egrep -l 'GE.[100|120|140|159].' /home/test_dir/* xargs egrep -l 'EA.[NT|[HD|HS|QR].')" ]; My problem ...
4
votes
1answer
583 views

command: ls /etc | sort | grep d* is yielding no results but ls /etc | sort | grep p* lists entire directory

I am playing around with piping and grep tonight. I know that grep uses regex and that * means 0 or more occurrences of the preceding character. So the way I understand it is that if I do the ...
6
votes
1answer
440 views

find words with all vowels in order from a file

I have a large dictionary file with 300,000+ words in it and I'm trying to find all words with the vowels aeiou in that order and have only exactly 5 vowels. My current attempt does not seem to be ...
-3
votes
2answers
127 views

Extract certain column from CSV files [closed]

I have a directory with a group of CSV files. All files have the same column headers. I need to extract values in a certain column from all files. The common part in files names is ...
0
votes
1answer
65 views

Print lines if pattern is not matched

Print lines of File 1 only if they don't contain patterns specified in File 2 Exemple: $ cat File_1 L1 pattern1 L2 pattern pattern2 L3 pattern3 pattern L4 pattern4 $ cat File_2 ...
5
votes
2answers
262 views

How do you get fgrep to find the literal “--help”?

fgrep --help | fgrep "--help" returns just the whole fgrep --help, how do I return just the lines that have the literal "--help" in them? The quotes don't do anything, nor does \-\-help.
2
votes
1answer
29 views

Grep patterns in selected lines

How to keep rows containing pattern 1 only if the next line contains pattern 2 and starts with pattern 3 ? Exemple: keep line starting with an A only if the next line starts with a B and contains ...
2
votes
2answers
70 views

Will grep go faster with line breaks?

I have some big files that I have changed into "standardized form", removing line breaks. I want to speed up greps on those files. I know that you can optimize grep by doing grep 'partofpattern' | ...
5
votes
4answers
221 views

How to replace m part of Lines with n part of Lines?

I have a file "test" like this: RewiteEngine On RewriteCond %{REMOTE_ADDR} !^192\.168\.1\.7$ [NC] RewriteCond %{REMOTE_ADDR} !^192\.168\.1\.8$ [NC] RewriteCond %{REMOTE_ADDR} ...
-1
votes
2answers
62 views

How to use grep to find all instances of one .txt file in another?

How would I use grep to compare if any line from one .txt document occurred in another? Further how would I use grep to find out the opposite? Would it be grep -v?
2
votes
4answers
184 views

Matching string with a fixed number of characters using grep

I am trying to find all 6 letter words using grep. I currently have this: grep "^.\{6\}$" myfile.txt However, I am finding that I am also getting results such as: étuis, étude. I suspect it has ...
4
votes
1answer
41 views

grep variable-length optional text

I would like to search for edge-anchored text that has a block of preceding optional text, any amount of which can be included in the match. For instance, supposing I am trying to find ^xyz but would ...
3
votes
1answer
156 views

How to export data in the terminal to a file (e.g. csv file)

I am a complete beginner in using Linux and I would like to know how to export a bunch of data in the command line to a csv or spreadsheet file (or even text would work). Right now I am simply using ...
3
votes
0answers
20 views

agrep with directionally biased penalties

I am using tre-agrep, an implementation of agrep, to perform approximate pattern matching. This utility searches for matches based on Levenshtein distance, and the user can configure the penalty ...
0
votes
1answer
31 views

For a given directory, how do I concatenate the tail end of recently modified files to a new file?

In case there's a better solution to the problem, my goal is to be able to quickly analyze ALL recent apache activity in /usr/local/apache/domlogs. The usefulness of this is when the server load is ...
0
votes
2answers
36 views

How to list similar lines?

The delimiters could be: " "; "_" INPUT: foo#foo_ehh113#The password of user 111 will expire within the next seven d foo#foo_ehh204#The password of user 111 will expire within the next seven d ...
0
votes
3answers
90 views

grep substring between quotes

Let's say I have a string like this: title="2010-09-11 11:22:45Z" How can I grep the date itself and disregard the quotes/title/Z? The file can contain more strings like: randomstring ...
5
votes
4answers
86 views

Search a pattern and print preceding lines starting with another pattern

I need to grep for a pattern and once I find it, I need to look for another pattern preceding that and print all those lines in between those. Better example: 1 a 2 a 3 a 4 a 5 a 6 b 7 c 8 d 9 xyz ...
7
votes
4answers
2k views

Find the exact string with grep

by way of example, I've a big text file with many email address, using bash I need search/verify that an email exists (or no). Should be use (only) the "anchors"? grep '^user1@example.com' text_file ...
0
votes
1answer
72 views

how do I recursivley grep (or otherwise search for) hex strings

Long and short I'm trying to track down some files left by evil scum on a server. fgrep -r "STRING" /path/here has been working well for finding general stuff. However, how do I search for hex ...
7
votes
2answers
489 views

Why is `tac file | grep foo' (piping) faster than `grep foo < <(tac file)' (process substitution)?

This question was motivated by "Reverse grepping", about grepping a huge file from bottom up. @chaos said: tac file | grep whatever Or a bit more effective: grep whatever < <(tac file) ...
1
vote
2answers
89 views

List all the html tags in a file

I want to know if there is a way to list all the html tags in a file. Lets say I have a file file.html <html> <head> <title>Test</title> </head> <body> This is a ...
32
votes
4answers
2k views

Reverse grepping

Let's say, I have a really big text file (about 10.000.000 lines). I need to grep it from the end and save result to a file. What's the most efficient way to accomplish task?
0
votes
3answers
48 views

Grep display both matched and umatched lines [duplicate]

How can I use grep command to display both matched and unmatched lines? Matched line should be in red and other lines should be in normal color. Is there a grep option available to do that?
2
votes
3answers
207 views

Reverse match in sed, replace opposite of what was found

Say I have this output from my syslog, precalculated src_hash => 20 bytes @ 0x7f811c001e20 A6 2D E5 CD 2A BA F0 42 56 66 19 D4 61 1A E3 A0 .-..*..BVf..a... C7 5E 5F 77 ...