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

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2
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2answers
122 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' | ...
2
votes
1answer
42 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 ...
3
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1answer
2k 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 ...
-1
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2answers
163 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
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4answers
2k 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
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1answer
99 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
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0answers
23 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
95 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 ...
11
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3answers
27k views

How do I count the number of occurrences of a word in a text file with the command line?

I have a large JSON file that is on one line, and I want to use the command line to be able to count the number of occurrences of a word in the file. How can I do that?
0
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2answers
39 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
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3answers
694 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 ...
7
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2answers
785 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) ...
7
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4answers
17k 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
177 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 ...
1
vote
2answers
294 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 ...
0
votes
3answers
195 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?
3
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2answers
9k views

Search string in many files on HP-UX

I need to find which files (they can have space in the filename) of a directory contains a string using only sh and system's commands (Perl is not an option). For a few files, this command works ...
3
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5answers
152 views

How to “grep” a string of a returned result

How to grep the number 50.0 from the string temp=50.0'C In JavaScript I can use the expression /temp=(.*?)'C/ to get it. But I cant get it running in grep.
2
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3answers
3k views

Command-line tool to search docx files

Is there a command-line tool to text-search a docx file? I tried grep, but it doesn't work with docx even though it works fine with txt and xml files. I could convert the docx to txt first, but I'd ...
0
votes
3answers
931 views

Grep finding phone numbers in files

How would I look for files in the /etc directory (but not subdirectories) that contain a standard United States long distance phone number, written using the pattern of 1-###-###-####, where each # is ...
0
votes
2answers
6k views

Solution to integer expression expected [closed]

So I when I run this code on my mac there are no errors, and it provides me the perfect output. But when I run it on Ubuntu or CentOS i get the following error integer expression expected ...
1
vote
3answers
1k views

How do I Copy and Paste lines between a start and end keyword?

I have two text files, and I want to copy a bunch of lines from one to the other. File one has a list of packages, and I want to copy it to list two. This list of packages isn't at the start of file ...
2
votes
2answers
243 views

How do you construct a grep & command to match a number of patterns depending on how many are provided at runtime?

I have exported some MS Word documents to plain text and use this function to parse the contents of the .txt files in the current directory: mo1 () { for i in *.txt; do echo "File: $i" grep ...
2
votes
3answers
486 views

bash - extract filenames from html file containing multiple links

I have downloaded an html file autogenerated by a script on a webpage. The file contains multiple links, including links to images I am trying to extract the full names of the images, for example ...
3
votes
1answer
4k views

How do I use grep to find a text string in files in sub folders of a parent folder without -r switch

I'm using Solaris 10 and have two grep versions one in /usr/bin and one in /usr/xpg4/bin. I have been searching for an answer on how to search for text within files within sub folders of a parent ...
6
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1answer
2k views

Why do I have to escape a “dot” twice?

I know that we can escape a special character like *(){}$ with \ so as to be considered literals. For example \* or \$ But in case of . I have to do it twice, like \\. otherwise it is considered ...
1
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2answers
92 views

Have grep output spaced for each file

When I do grep on a bunch of files, and several file have the word I am looking for, the output is hard to read as it's one after the other. Is there anyway to insert additional \n's after the ...
3
votes
1answer
179 views

Grep with spaces suddenly doesn't work

When performing a grep like: $ tail -f apilog_2014.07.09.log | grep "HELLO" | grep "99999" I get the desired output: 12:22:35 server apache2: HELLO FRIEND 99999 12:22:35 server apache2: HELLO ...
1
vote
1answer
168 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 ...
0
votes
2answers
106 views

How to count number of instance of a word starting at another word

I need to grep the MySQL-error log starting at today's date formatted like: `date +"%y%m%d"` (140710) And look for all instances of the word partitioned. I've tried various things to no avail. ...
1
vote
6answers
512 views

Print word that doesn't contain character

My file is in the following format: this!,is!,another!,test,yes! this!,is!,another!,column,yes! no,not!,another!,column My output should be: test column no It shouldn't contain the '!' ...
3
votes
1answer
41 views

annotate “include” file for grep with comments?

I do a grep sort that includes certain strings. That is, give me the lines in a file that DO contain certain strings. As in grep -fv include file > out That command looks in file and sends to ...
5
votes
1answer
197 views

List overlapping instances of a pattern

I'm trying to capture a string and the 21 characters preceding it then output this to a new file. This is what I'm using currently: grep -o ".\{21\}gt" ../data/fastadata.txt > primerdata.txt ...
2
votes
1answer
521 views

Using bzgrep recursively

I wanted to use bzgrep to find to text in bzip2 files. I expected bzgrep to work as grep, but on bz2 files. So I tried bzgrep -r "mypattern" . to find text in my bz2 files. Instead of the ...
3
votes
1answer
63 views

Matching several patterns on one line

I often use a program called tty0tty, which creates a null modem using PTYs. Now I want to make it part of an automated process. When I start tty0tty it prints (/dev/pts/1) <=> (/dev/pts/2) ...
8
votes
2answers
397 views

Redirecting output depending on grep regex

I am using gradle run to start a REST server. The output of the REST server looks like this: XXX.XXX.XX.XXX - <moreinfo> randomtext randomtext XXX.XXX.XX.XXX - <moreinfo> XXX.XXX.XX.XXX - ...
6
votes
5answers
260 views

Strategy to extract movies's name from this ununiform dataset?

I am working on a movie database problem to improve regular expressions, this is the problem I'm running into. My dataset looks like this: Movie Name (variable space and tabs) year Movie1(can ...
4
votes
4answers
1k views

Match two words that is on the same line

The command that I have prints out two of the lines whenever FW_6.0.0 is found, below is the code: grep -oP 'FW_6.0.0, (.*)$' file Below is the output, both has the same value of FW_6.0.0 ...
4
votes
2answers
4k views

To grep 20 characters after and before match

I have the problem that I get too much information after the match for grep -RnisI --color=auto "pseudomonas" * I want to get only like 20 characters or 10 words after and before the match. What ...
2
votes
1answer
68 views

Context of the matching regular expression

I'm using egrep with the -o option in order to just get the matching part of the line, e.g. cat /usr/share/dict/words | egrep -o '(aa|ii)' Now I'd like to see some context of the match, i.e. a few ...
1
vote
2answers
793 views

Extract Values from simple html file via grep/awk

I have another grep/awk/sed issue within the attached HTML code below. Given is a simple HTML file with table inside. The HTML is generated by a smart meter (household energy meter). Inside the html ...
6
votes
2answers
281 views

Grepping for a block of text with parts that can be optional

I have multiple entries that describes an event in a very large log file, say A.log. I would like to do two things with the event entries in the log file: Count the number of occurrences of each ...
1
vote
2answers
356 views

Using grep to get UUID

How can I get the uuid of eth0 connection out of the output of nmcli -p c using grep? Output of nmcli -p c: $ nmcli -p c ...
4
votes
1answer
553 views

Literally grep the only word in a line

I know grep -F can search for literal strings, but I want to do something like while read word; do grep -F "^$word$" FILE; done < wordlist i.e. the words need to be treated literally, at the ...
2
votes
1answer
81 views

move the search content to different directory

I am on Oracle Solaris. I am using: grep "searchstring" filename.* above command returns my search result. Now I want to move the all the files in above search result (all the files not the ...
5
votes
2answers
158 views

Why does a grep reboot the machine?

On a RHEL 6.5 Desktop, if I use: sudo grep -r foo /* my desktop reboots. Q: Why?? How to debug this? It's the third time my Desktop reboots because of this :D
0
votes
1answer
281 views

Show output only if both words match using grep [duplicate]

If packagehello does not match, the output is still displayed. Aim: to see no output in situation 2 Situation 1: user@hostname ~]$ sudo yum list 'package*' packagehello packagehello package2world ...
1
vote
3answers
184 views

Extract line number of a file which is having a non zero value before a specified string

I'm having a file which contains following data 1. verification: 10 passed 0 failed 2. verification: 10 passed 0 failed 3. verification: 10 passed 1 failed 4. verification: 10 passed 3 failed 5. ...
4
votes
3answers
631 views

cascaded grep matches color code as pattern

I am piping output of one grep comand into another grep. The first grep is using --color=always, so that the first match is colored. In practice, that means that the match is enclosed between two ...
1
vote
4answers
3k views

Printing a new line using awk

I have a load of files in which I need to take out specific rows and then put the data I've taken out into a spreadsheet. An example would be my file shows: Name: w Age: x Height: y Weight: z I ...