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

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7
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5answers
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grep skip n lines of file and only search after

I have a huge log file and want to grep the first occurrence of a pattern, and then find another pattern right after this occurence. For example: 123 XXY 214 ABC 182 558 ABC 856 ABC In my example, ...
0
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2answers
23 views

Find a string between spaces

I was searching around the site and couldn't find a solution for the following, despite it's a simple thing. So let me share... If you know a better solution, please share I have the following log ...
29
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2answers
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Why doesn't grep ignore binary files by default?

The manpage for grep describes the -I flag as follows: -I Ignore binary files. This option is equivalent to --binary-file=without-match option. It also says this about binary files: ...
0
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1answer
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Copying files containing specific text preserving directory structure

Using the code in this answer, I can easily copy a file containing specific text from one folder to another. With the -r option I can also search inside directories recursively. The result is that ...
3
votes
6answers
184 views

grep with continuation lines

How can I grep/awk/sed a file looking for some pattern, and print the entire line (including continuation lines if the matched line ends with \? File foo.txt contains: something whatever thisXXX ...
2
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4answers
209 views

Using Grep -o or Sed/Awk to Grab Snippet from Middle of String

I am watching log traffic and see regular abuse of the various image search engines, Bing particularly. Example URL: ...
1
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2answers
49 views

searching for files with multiple strings (all inclusive, not one or the other ) and print line numbers

I want to search for 2 (or more) strings across the files of a certain directory and print the line numbers. The search results should include only those files where all the mentioned strings are ...
1
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3answers
2k views

Find files containing one string but not the other

I am in a folder with lots of .txt file, I would like to find all the files which contain stringA, but don't contain stringB (they are not necessarily in the same line). Does anyone know how to do ...
1
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2answers
2k views

How to do a grep on remote machine and print out the line which contains those words?

I have few logs files in my machineB under this directory /opt/ptd/Logs/ as shown below - My logs files are pretty big. david@machineB:/opt/ptd/Logs$ ls -lt -rw-r--r-- 1 david david 49651720 Oct 11 ...
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4answers
942 views

Match exact string using grep

I have a text file: deiauk 1611516 afsdf 765 minkra 18415151 asdsf 4152 linkra sfsfdsfs sdfss 4555 deiauk1 sdfsfdsfs 1561 51 deiauk2 115151 5454 4 deiauk 1611516 afsdf ddfgfgd luktol1 4545 4 9 luktol ...
2
votes
1answer
70 views

grep misreads pattern from variable

I have a problem with escaped pattern put in grep. My test file is: export_cc = ${dir}/aaa/bbb/ccc export_cc = ${dir}/aaa/bbb/eee export_cc = ${dir}/aaa/bbb/ddd export_cc = ${dir}/aaa/bbb/fff ...
12
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6answers
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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. ...
26
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6answers
13k views

What makes grep consider a file to be binary?

I have some database dumps from a Windows system on my box. They are text files. I'm using cygwin to grep through them. These appear to be plain text files; I open them with text editors such as ...
14
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2answers
43k views

How can I assign the output of a command to a shell variable?

I want to assign the result of an expression to a variable and concatenate it with a string, then echo it. Here's what I've got: #!/bin/bash cd ~/Desktop; thefile= ls -t -U | grep -m 1 "Screen Shot"; ...
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4answers
104 views

grep NOT maching exact string

I have a file 1 IF 9/1 Joe 2 IF 9/1 Marry 3 IF 9/12 Larry 4 IF 9/15 Page And I want to print only those lines that doesn't mach IF 9/1 using grep. I know that I could do that using grep -Fvx 'IF ...
0
votes
3answers
123 views

Find all words beginning with Q

How do I search a text file and list all the words begining with Q? The file I am searching is Python source code. The closest I have found to a soulution is this question but that is not what I ...
1
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1answer
52 views

finding lines in a file matching patterns defined in another file

I have two files file1.txt kepaul jack mike david and file2.txt 1 london smith 12564 2 miami jack 51616 3 la mike 165156 4 london kepaul 54654 5 miami grag 46546 and I need to print to a new ...
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2answers
53 views

Displaying a list of all *.java

Display a list of all java files which name is *.java in your current working directory which contain the string Example, regardless of the case sensitivity of the latter's individuals letters. ...
2
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1answer
156 views

How to grep whitespace exclude new-line character?

Today I need to check which lines of my files containing trailing whitespace. And I figured out a solution: grep -Enr --color "\s+$" ./ This works well except for those lines containing non-Unix ...
1
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0answers
19 views

Interpreting regex wildcards with grep [duplicate]

This is a really simple question, but even after reading about wildcards/regex, I can't seem to grasp entirely what the differences between these commands are: grep . test.txt this one will look ...
4
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2answers
156 views

How costly is case insensitive search as compared to case sensitive search?

I dont think grep -i is exponentially (wrt to the number of characters to be grepped) more costly (time wise) than a normal grep because the run times are not too different. But theoretically it ...
1
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1answer
41 views

How to filter a basic csv by columns

How do I filter by third column of the following file list.txt [[ list of people ]] billy baxter - @baxter - b.baxter@woods.com james woods - @woods - j.woods@someother.com I currently have cat ...
0
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1answer
53 views

grep to compare files not working

I successfully used: grep -wFf inputqueries.txt seachedfile.txt > results.txt to search searchedfile.txt for each query in inputqueries.txt. inputqueries.txt looks like: 213.183.56.186 ...
33
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5answers
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Count total number of occurrences using grep

grep -c is useful for finding how many times a string occurs in a file, but it only counts each occurence once per line. How to count multiple occurences per line? I'm looking for something more ...
2
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1answer
368 views

What does this grep expression mean? [closed]

\*.\?[A-Z]\?.* This grep command is cryptic. I understand that it is supposed to search for uppercase commands.
5
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5answers
405 views

Run `grep` excluding a file in a specific path

I want to exclude the file ./test/main.cpp from my search. Here's what I'm seeing: $ grep -r pattern --exclude=./test/main.cpp ./test/main.cpp:pattern ./lib/main.cpp:pattern ./src/main.cpp:pattern ...
1
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1answer
41 views

Get `grep` to not output file name

When I use grep -o to search in multiple files, it outputs each result prefixed with the file name. How can I prevent this prefix? I want the results without the file names.
5
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2answers
338 views

How to search for text in a file ignoring newlines?

I'd like to search for text that may be split over several lines in a file. A grep that would ignore line breaks and return the matching span of lines. e.g. I would be searching for is an example ...
4
votes
3answers
355 views

Extracting unique piece of text from file with awk, sed or grep

From the output of pactl list sink-inputs, I need to grab the sink input number for VLC. Before that, I'm trying to extract the piece that contains the output for only VLC. All the methods that I ...
1
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2answers
110 views

Extract some columns from grep output

I've run the command grep -a --binary-file=text "DLDM" /home/path/ldm.log-$1* | grep -a "$line" and the output is something like this :- /home/path/ldm.log2015:"unix","20150518 ...
31
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8answers
7k views

Is there a way to modify a file in-place?

I have a fairly large file (35Gb), and I would like to filter this file in situ (i.e. I don't have enough disk space for another file), specifically I want to grep and ignore some patterns — is there ...
1
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1answer
194 views

what is meant by “^$1” in shell script?

#!/bin/sh #emp3.sh: using if and else # if grep "^$1" /etc/passwd 2>dev/null then echo "pattern found - job over" else echo "pattern not found" fi in the above programme what is "^$1" and ...
0
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1answer
52 views

grep searching groups

I'm trying to learn to use grep groups, like sed \1\2\3, but have a problem. For example I filtering /etc/services file to separate all ports. What I do: ~$ grep -E '[0-9]{1,5}/(tcp|udp)' ...
4
votes
1answer
149 views

What is the opposite of “grep”?

Say I'm printing out a long series of strings, and instead of only showing lines containing a certain pattern (which one uses "grep" to do), how do I filter out certain patterns?
1
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2answers
76 views

How to perform grep on 'man unix_command'?

Often while going through the output of man man awk I Need to perform grep, for e.g. in man awk, I need to find the definition of a particular flag, variable etc. Can anyone tell me, what would be ...
1
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5answers
73 views

Grep 2 different requirements in one command line statement

How would I print the last 3 lines that have the string #include from tester.c and if fewer than 3 lines contain the string, print the entire file. So far I have: grep "#include" tester.c | tail -3 ...
2
votes
2answers
57 views

Can't get GNU grep 2.12 to handle LF character in regex expression

I've been at it for over an hour, but can't find why it's not working. I'm searching an HTML document for "\nSome text". Simple enough. But he following commands won't work: grep -Po ...
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1answer
27 views

Grepping entire system but dodging process files and the like [duplicate]

I have so many systems I need to do and I find it really impractical for me to grep everything/folders individually.
1
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0answers
92 views

Grepping multiple instances of a string, with context, from a file

I have a MySQL dump file, which is mostly INSERT statements. I want to grep out instances of the string 'media' from a field in a particular table, with +/- ~10 characters of context. The string might ...
1
vote
1answer
44 views

Conditional awk across 4 columns

I have a tab-delimited file with 9 columns as follows: 1 25555818 T 14 0 0 0 14 0:0:0:14 2 25555819 T 14 7 0 0 7 7:0:0:7 3 25555820 G 13 0 0 13 0 ...
1
vote
4answers
373 views

Wildcards for filepaths aren't working in grep [duplicate]

I need to grep words like these: ABC-DEF AB2-DEF AB3-DEF AB-DEF So I was trying: grep AB*-DEF grep -w -AB*-DEF grep -w AB*DEF But neither of them are working. Please help.
6
votes
6answers
13k 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 ...
-3
votes
1answer
50 views

grep-ing - I think [closed]

I have a multitude of files (2TB) which all have word data in them. All the data follows the same format but the information slightly changes I need to be able to pull out specific data from the files ...
2
votes
2answers
137 views

Extract substrings from each line. These substrings are in comma separated, “name=value” format

I have lines in a file that are comma separated. There are no column headers, it's mostly comma separated 'name=value' pairs. Here is some test data: ...
10
votes
5answers
8k views

How do I recursively grep through compressed archives?

I'm trying to find out what modules use Test::Version in cpan. So I've used minicpan to mirror it. My problem is that I need to iterate through the archives that are downloaded, and grep the files ...
1
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2answers
35 views

Using Unix, when detecting a pattern, we need to detect its corresponding other pattern

When detecting the line containing the pattern night, we need to detect its corresponding line containing the other pattern === which is just occurring at a higher line as shown below. File content: ...
7
votes
3answers
511 views

How to use [\w]+ in regular expression in sed?

I am on Windows, but I guess my question is still rightly placed here. C:\Users\User>grep --version GNU grep 2.6.3 C:\Users\User>sed --version GNU sed version 4.2.1 I noticed that the ...
2
votes
3answers
58 views

Search a String in a directory- Get output without filename

I am executing the below command to display the lines which matches the pattern. find ./files/ -name "*.txt" -print0 | xargs -0 grep "5|20150507" And output is ...
6
votes
2answers
789 views

bash - why does \x0d\x20 erase the line

This is the view from gedit editor: and the view from vim editor: I then try to grep it, it did grep successfully if i put Log instead of Tog, but the output is corrupted: [xiaobai@xiaobai grep]$ ...
3
votes
4answers
166 views

Find the last occurence of a string in a given filetype in all subdirectories

I have multiple sub-directories each with different depths. I need to search for the last occurrence of a string in a specific filetype (say *.out). How can I accomplish this? I have tried: grep -r ...