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

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27
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2answers
9k views

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
votes
1answer
24 views

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 ...
2
votes
6answers
159 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
votes
4answers
100 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
vote
2answers
32 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 ...
0
votes
1answer
1k views

How to execute grep in tcl for getting XYZ-123 type pattern

How can I execute this grep command in TCL? grep '[A-Z][A-Z][A-Z]\-[0-9][0-9][0-9]' file1 > file2
1
vote
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
vote
2answers
1k 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 ...
1
vote
4answers
142 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
48 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
votes
6answers
2k 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. ...
25
votes
6answers
11k 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 ...
12
votes
2answers
36k 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"; ...
-1
votes
4answers
75 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 ...
10
votes
7answers
17k views

How to read first and last line from cat output?

I have text file. Task - get first and last line from file after $ cat file | grep -E "1|2|3|4" | commandtoprint $ cat file 1 2 3 4 5 Need this without cat output (only 1 and 5). ~$ cat file | ...
0
votes
3answers
87 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
vote
1answer
39 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 ...
-4
votes
2answers
40 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
votes
1answer
49 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
vote
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
votes
2answers
155 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
vote
1answer
38 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
votes
1answer
45 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 ...
29
votes
5answers
81k views

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
votes
1answer
115 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
votes
5answers
167 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
vote
1answer
33 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
votes
2answers
119 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 ...
3
votes
3answers
271 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
vote
2answers
45 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 ...
30
votes
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
vote
1answer
93 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
votes
1answer
41 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
86 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
vote
2answers
65 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
vote
5answers
70 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
50 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 ...
-1
votes
1answer
25 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
vote
0answers
60 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
37 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
236 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
12k 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
49 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
105 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
7k 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
vote
2answers
32 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
238 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
55 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
723 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
71 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 ...