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

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Grep all string which do not starts with number(s)

I'm looking for grep to show all characters which do not starts with numbers. I have done something like this: grep -v '^[1-2]*[a-zA-Z]?' -o but it do not work. Do you have any idea for some reg ...
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2answers
55 views

A batch that cout the number of occurrences

I've to extract the number of words using each letter of the alphabet from A to Z. The script that i've to create create take as parameter the name of the dictionary file to analyze and will be used ...
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1answer
39 views

What is the meaning of (^| )ABC( |$) as an extended REGEX ?

I came here across the command grep -E '(^| )ABC( |$)' file1 I am confused how to interpret the regular expression therein, because I know the ^ and $ character as beginning and end signifier, but in ...
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1answer
249 views

How to grep exact word with only space as word separator

For Example: I have file like following: AA ABC-AA-AA AAA ABC-AA ABC.AA ABC AA ABC.A AA If I use grep -w "ABC" file1, I am getting all the lines. But I should only get 3rd line: ABC.AA ABC It is ...
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2answers
55 views

Match lines not ending with an specific character

I have been learning linux commands and got this error. My text is here: Fred apples 20 Susy oranges 12 Mark watermellons 12 Robert pears 4 Terry oranges 9 Lisa peaches 7 Egemen aaaa 12 Susy oranges ...
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List the files containing a particular word in their text

I would like to list the files recursively and uniquely that contain the given word. Example: Checking for word 'check', I normal do is a grep $ grep check * -R But as there are many occurrence ...
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4answers
250 views

Grep pattern inluding dashes and restricting to a filename extension

I am trying to use grep to find some tex files containing the pattern ->-: grep -R -- "->-" *.tex But this doesn't work. If I do: grep -R -- "->-" instead, it works, but is really slow ...
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Using 'grep' to search for a specific pattern [duplicate]

I'm playing with the Linux terminal and I have to do a exercise which states that I have to find inside a file for any line that contains at least an a, b and c, it doesn't matter it the lane has 2 a, ...
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How to pipe the result of a grep search into a new vi file

I'm using grep -e Peugeot -e PeuGeot carlist.txt to search through carlist.txt and pull out some items and I presumed that grep -e Peugeot -e PeuGeot carlist.txt | vi would pipe it through for me but ...
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3answers
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Using The Grep Command

I have two simple questions regarding the use of the grep command that I'm sure that someone can help me with. What I want to do is: show the total lines (processes) running as me except for the ...
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1answer
51 views

How to find with grep lines that end in a certain string?

I know that to find a REGEX that ends in a certain string I have to write "string$". Although I tried the following variations of grep : cat foo | grep "string$", cat foo | egrep "string$", grep -E ...
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Why is this command not working: “ps aux | grep xscreensaver”

I didn't see any hits about this on google, so I'm asking you: I just tried to run this command in an ssh session, local is Debian Wheezy KDE, remote is Fedora 21 Gnome: ps aux | grep xscreensaver ...
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1answer
148 views

grep (/sed/awk) month range

I've looked around for solutions to this, but it's sort of difficult to search for the solution to such a specific problem (lot of words to put in Google). So, I have a file with data that looks like ...
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2answers
63 views

What regular expression in grep searches for strings of three same letters in a row?

I have a text file and I am using the grep command with a regular expression to get only the lines which contain three same successive letters, e.g.: aaa bbb ccc ddd What regular expression do I ...
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2answers
54 views

How to “grep” for line length in a given range?

I need to get only the lines from a textfile (a wordlist, separated with newline) that has a length range of minimum or equal than 3 characters, but not longer or equal then 10. Example: INPUT: ...
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3answers
310 views

How do I use the regular pattern operator {m,n} in grep?

I have a text file, from which I need to select only those lines, which include the string "tt". So I tried this on the command line: grep "t{2}" textfile Allthough I know the textfile contains ...
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2answers
40 views

how do I find the location of mysql drivers on CentOS 7?

MariaDB is installed on a remote CentOS 7 server. How can I find the location of the nearest equivalent to mysql-connector-java-5.0.8.jar in the server's file system? grep seems to only search ...
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2answers
760 views

Speed up zgrep on a multi-core computer

I'm running zgrep on a computer with 16 CPUs, but it only takes one CPU to run the task. Can I speed it up, perhaps utilize all 16 cores? P.S The IO is just fine, I could just copy the gzipped file ...
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3answers
60 views

Run fgrep multicore mac os x

I'm running this command on my Mac OS X on 8 cores: for i in $(cat file1);do grep "$i" file2; done > output.txt My file2 is 9 million lines so it takes a lot of time. Is it possible to use all ...
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1answer
46 views

Only grep for lines that only contain alphabetical characters

Question: How can I grep for lines that ONLY have the following characters (all in lowercase)? aábcdeéfghiíjklmnoóöőpqrstuúüűvwxyz example: INPUT: árvíztűrő tükörfúrógép árvíztűrő ...
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How to grep a line with unknown number of its indented lines

I often need to grep a line with its indented sections. For example, if the indented line number may be known, we would achieve this goal with the following: $ lspci -vq | grep -i wireless -B 1 -A 5 ...
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3answers
69 views

How can I output sample rows from a .csv?

I'm doing a lot of data merge printing and would like to be able to output, say, 10 samples from a large database. My goal would be to extract the 10 rows spread evenly from the supplied .csv ...
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1answer
42 views

Regex for matchng anything between parenthesis

I have the following regex so far: printf "this is (test.com)\n" | grep -Po '(?<=\().*(?=\))' The above regex will print the desired output, which is test.com As far as I am adding new ...
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2answers
35 views

How to match multiple lines starting with a TAB, and the line before the 1st one in a group?

I've got some third party log files I'm trying to pull errors out of on the command line. The logs look like this: time=1 time=2 time=3 at com.test.com.... at com.test.com.... at ...
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1answer
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grep --exclude-dir behaviour: a bug or a feature?

I have noticed an annoying change in grep -r --exclude-dir behaviour. Consider the following test: mkdir -p ./d1/d2 echo 'randomtext' > ./d1/d2/testfile grep -nr --exclude-dir ./d1/d2 ...
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2answers
223 views

find field pattern in a csv file then count unique field values

I am using Cygwin (bash) to create a script to find, group and count fields in multiple CSV files. Each row will have comma-separated fields with each field following a similar convention. There is a ...
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2answers
92 views

Grep matching cell of the csv file and index of that row

I have csv file and I want to see numbers that start with 0.99 and their row's index which is the first cell of that row. This is what I have so far: cat fil.csv | grep '0\\.99'| tee > (cut -d, ...
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2answers
48 views

How to add a column if line contains string?

If I have a tab-delimited file containing the following lines: Sample1-Baboon 1 2 3 4 Sample2-Human 1 2 3 4 Sample3-Human 1 2 3 4 Sample4-Baboon 1 2 3 4 How can I add a new column ...
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3answers
736 views

Exclude files that have very long lines of text from grep output

I often run grep commands to find things in my code, but the problem with web projects is that there will often be compressed JavaScript and CSS files which create one huge line of text, so that if a ...
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Grep command that finds/excludes all line where a separator character appears a certain number of times?

Is there a Unix utility to restrict a file or directory listing to given minimum and maximum number of levels deep? I have a git command which displays a unique listing of the directories where files ...
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1answer
82 views

Reading a string till a key word and replacing from there with another string

I am new to UNIX and am practising shell scripting. I have an application where I need string searching and replacement. There are some lines in a file 1 and file 2. I have a search key word. If the ...
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1answer
58 views

Script to `grep` a file with variable [duplicate]

while read wholeline do echo ${wholeline} --outputs John Jones #grab all the lines that begin with these values #grep '^John Jones' workfile2 --works, prints contents of workfile2 where the ...
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2answers
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Characters visible in vi, but not in cat.

I have a 300 lines file with ^@ character between each characters in the file. (I cannot post the entire contents for security reasons, so I am pasting only the first line) [mercury@app01 ftp_logs]$ ...
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2answers
59 views

Multiple grep commands with sort

I have a text file containing a list of student grades: Andrew cooking A Andrew cooking B Andrew computing F Steven java C Steven python E Ben C++ D Ben python C Jamie java E Jamie C++ E Jamie C++ B ...
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8answers
635 views

Using 'grep' to find lines that contain all of three specified characters in any order [duplicate]

We have a document which contains lines and we have to find if [a|b|c] appears at least once in every line no matter which order. For example: Input: abc bca cab hhfdhdhfabjfdjdjff acjfdjdfjdf ...
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1answer
54 views

Find which file contain a particular keyword using `grep`

Suppose I know I have to change myhostname = abc.domain.lcl to myhostname = abc.domain.glbl directive but I don't know in which file exactly the directive myhostname is in (i.e., say I have never ...
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2answers
26 views

How to select specific sets or sturture from a file, if struture contains specific string?

I want to extract the sets with having specific string, for example: file abc.txt contains abc 123 abcd 1234 abcde 12345 abc 123 abcd 123 abcde 12345 abc 123 abcd 1234 abcde 12345 Now from the ...
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4answers
798 views

Use “grep” to match text in multiple files

I have data in multiple files. I want to find some text that matches in all files. Can I use the grep command for that? If yes then how?
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3answers
9k views

How to show lines after each grep match until other specific match?

I know that by using the "-A NUM" switch I can print specific number of trailing lines after each match. I am just wondering if it's possible to print trailing lines until a specific word is found ...
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1answer
49 views

How can I recursively grep through several directories at once?

I use grep -r all the time to find occurrences of a string within files in a given directory: $ grep -r "string" app/assets/javascripts > app/assets/javascripts/my_file.js: this line contains my ...
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2answers
173 views

Capture in shell variables the arguments after a command (between brackets)

Suppose I have a file that contains, among many other things, \command{arg1,arg2,arg3} (arguments been paths, expressed with /, ., characters and numbers) But that a user can as well call it ...
3
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2answers
11k views

grep and escaping a dollar sign

I want to know which files have the string $Id$. grep \$Id\$ my_dir/mylist_of_files returns 0 occurrences. I discovered that I have to use grep \$Id$ my_dir/mylist_of_files Then I see that the ...
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1answer
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is there a way to see a listing of packages ONLY from Debian-experimental?

I am on Debian testing/Jessie and I have debian-experimental as well as in my /etc/apt/sources.list. So I am looking to list packages in two ways :- a. List all the packages which are in ...
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5answers
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What is the difference between `grep`, `egrep`, and `fgrep`?

Can any one tell me the technical difference between grep and egrep, and fgrep and provide a suitable example? When do I need to use grep over egrep and vice versa?
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Why does regex with \\$\{ work with egrep, but not with sed?

Given a text like this ./RFF_09 -f${FILE} -c${COND} inside a file, this egrep command will correctly match: egrep './RFF(.*) (.*)-c\\$\{COND\}' file but this sed command will not sed -n ...
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4answers
3k views

Count tabs per line in text file with utils

I have a tab-tabulated file. I would like to check if every line has the same number of tabs. For first step, I'd like to print the number of tabs for each individual line. I've tried grep -o '\t' ...
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1answer
3k views

grep directory names, filenames, and contents all at once?

I'm writing a module for drupal. Its functionality is contingent on the directory name, certain file names, and function names being identical. I'm troubleshooting now, and I wanted to to a search ...
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4answers
249 views

Regex pattern search for alternating character case

How would I pipe the ls through grep to have an alternating character case, as output? For example: I have files (1) aAbBaBbA, (2) bAbBaA, (3) bbAb,(4) AAaBbAa,(5) BBBaaa, and (6) aBaB. I want to ...
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577 views

How to use grep and cut in script to obtain website URLs from an HTML file

I am trying to use grep and cut to extract URLs from an HTML file. The links look like: <a href="http://examplewebsite.com/"> Other websites have .net, .gov, but I assume I could make the cut ...
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1answer
36 views

Problem with grep on multiple files and not getting desired output

I am using the below command on a file to extract few lines based on chr# ( different chromosome numbers). This is just a single file am working on. i have 8 such files and for each file I have to do ...