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

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1answer
56 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 ...
4
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1answer
194 views

Blank lines when executing “grep | xargs” in a “find -exec”

I'm trying to list all directories of a web server that are blocked by Apache via a .htaccess (containing deny from all). I've managed to get the list of blocking .htaccess but when I try to extract ...
4
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1answer
97 views

grep --include acts like --exclude

I'm trying to make use of the --include option of grep, but it doesn't behave as I expect. Consider this simplified test: Setup me@de31:~/tmp$ cat file.h This is a .h file me@de31:~/tmp$ cat file.c ...
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2answers
60 views

How to exchange words in a filename using the shell?

One of my customers is a school. On their file server all projects have a directory with the same naming scheme. <last name>, <first name> <second name>? - <project ...
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0answers
108 views

what is grep -v -f /dev/null expected to do exactly?

Theory: grep -f somefile or grep --file=somefile will find all lines that match one of the patterns listed in somefile. If somefile is empty, nothing will match. With grep -v you list lines that do ...
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3answers
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Uniquely identifying java processes with same name

I have two java processes which run using the same file name, MyApp.jar (for example). /usr/java/latest/bin/java -jar MyApp.jar These jars exist in different places and use different ...
3
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5answers
438 views

Search among the content of a large number of plain text files?

I have a directory with 1,242,276 plain text files on my external hard drive. They are totally unorganized with meaningless numbers as their file names. The reason for that is because they were ...
3
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5answers
288 views

evaluate multiple patterns from program output and write into pattern specific files

I have a script outputting some value/numbers and I want to split those into two files. I am looking at something like: ./runme.sh | grep 'ook' >> ook.out | grep 'eek' >> eek.out Where ...
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424 views

How to get the lines that contain -R with grep

How can I find "-R" in files with grep? I tried grep "-R" *.GNU to get the lines that contain -R, but it returns nothing.
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5answers
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Output multiple files from a single grep?

I'm not very experienced in shell scripting, but I'm trying to understand how to grep for a pattern and for each file where there is a match write a file to disk that contains the matched line from ...
3
votes
2answers
319 views

grep on a variable

Lets say I have a variable line="This is where we select from a table." now I want to grep how many times does select occur in the sentence. grep -ci "select" $line I tried that, but it did not ...
3
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6answers
748 views

ls content of a directory ignoring symlinks

I have a directory in which I would like to list all the content (files and sub directories) without showing the symbolic links. I am using GNU utilities on Linux. The ls version is 8.13. Example: ...
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2answers
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How to use tail -f with grep to show surrounding lines

I would like to see the output in a logfile greped by only one domain but also the following two lines. Example: tail -f /var/log/apache2/modsec_audit.log |grep mydomain.de this shows all lines, ...
3
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3answers
259 views

How can I delete all text between curly brackets in a multiline text file?

Example: This is { the multiline text file } that wants { to be changed } anyway. Should become: This is that wants anyway. I have found some similar threads in the forum, but they don't seem ...
3
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4answers
1k views

How to use the grep result in command line?

When I use grep to find some text which I need, it will display lines containing a match to the given pattern. For example, # grep -r ".*Linux" * path0/output.txt:I hope you enjoyed working on ...
3
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4answers
233 views

Test if command accepts a specific option

What is the preferred way to test if a command takes an option? What are the caveats? As a motivating example, at login my shell aliases grep to add several --exclude-dir options but this option is ...
3
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4answers
542 views

Can I use grep matches to execute command?

I need to upgrade php from 5.3 to 5.4. I've installed it with rpm. I want clean install: delete all 5.3 packages, and install all necessary 5.4. Here is the command to see all installed packages: rpm ...
3
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2answers
882 views

Get 'less' to display filename

Something that seemed quite useful to me when looking for a certain var in a bunch of config files: less * | grep some_var So this returns the value of some_var without manually looking through all ...
3
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4answers
191 views

Identifying genes from a list of genes

I have a gene list file. Some thing like this SWT21 SSA1 NRP1 EFB1 TFC3 MDM10 I have another file which also contains the names of these genes in my list along with other ...
3
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2answers
4k views

grep: regex only for match anything between parenthesis

How do I match word only between parenthesis Input : this is (test.com) Desire Output : test.com
3
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5answers
965 views

How can I concatenate a single column of output into a list?

I'm using: ls /proc | grep -v "^[0-9].*" to get a list of all the files and directories in /proc that don't begin with numbers. The output is a single column list, i.e.: acpi asound buddyinfo bus ...
3
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3answers
208 views

Looking to grep or egrep year ranges from 1965-1996

I have a grep that works for some of the dates but having trouble getting my brain to make it fully functional. grep 19[6-9][5-6]$ filename it catches a few correctly but I'm looking to grab ...
3
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3answers
377 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 ...
3
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5answers
823 views

How to grep, then search and replace on the output?

I have some output from iconv, e.g. $ iconv -l | grep ISO | head -5 CSISO4UNITEDKINGDOM// CSISO10SWEDISH// CSISO11SWEDISHFORNAMES// CSISO14JISC6220RO// CSISO15ITALIAN// durrantm:~ How can I change ...
3
votes
2answers
904 views

Concatenate specific files into one single file

In a folder containing X files, I need to concatenate Y files (where X > Y) together into a single text file. I have the filenames (of Y files) that I need to concatenate. Can anyone please help me ...
3
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3answers
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How to search and replace text in all php-files in a directory and it's subdirectories

I am looking for a shell script that recursively traverses all .php files in a directory and performs a search & replace of a particular text pattern. The search pattern is quite long ( > 5000 ...
3
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2answers
138 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 ...
3
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5answers
133 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.
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3answers
246 views

Rearrange text file by prepending data rows with header row

I have a file whose content looks like this: 2009 150 0 0 0 0000 75.316 0.0400390625 0.00007 0.00000 0.8980 76.216 0.0400390625 0.00007 1.00000 0.9046 77.217 0.0400390625 ...
3
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2answers
244 views

How to use restricted characters in egrep?

I'm trying to use a regex in egrep on Centos 5.10, based on the one I made from this question on SO. T12345 .{1,100}[\n\r].{1,100}2014.03.04 I can successfully match the regex to the content in my ...
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2answers
1k views

“grep: Unmatched [” error when using regex

I'm trying to find a pattern similar to this: tail -n 100000 gateway.log | grep -B10 -A10 'Nov 22 11:13:56 Received Packet from [10.50.98.68' Where "11:13:56" could be any time. This is what I ...
3
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1answer
1k views

grep on line before the match plus the match

zzzzzzzzz aaaaaaaaa bbbbbbbbb & ccccccccc & ddddddddd hhhhhhhhh eeeeeeeee fffffffff & ggggggggg & in the above line, what i want is to grep/sed/awk (any method is fine) line that ...
3
votes
1answer
2k views

How to grep top most frequent error messages in a unix logfile

If I have a file example apache log file How to extract the top most frequent error messages in a unix log file with no timestamps the key is most frequent error message should come on top of the ...
3
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3answers
512 views

grep filter all lines plus one before each hit

I want to parse some output so I exclude all lines that contain either foo or bar, as well as all lines immediately preceding those lines. For example: echo " 1 some line 2 line to exclude because ...
3
votes
1answer
589 views

Output of `java -version` not matched by grep or awk

On my Linux machine, it isn't clear to me why if I do the following then I don't get only the version string ("1.5.0_32"). # java -version | grep version | awk '{print $NF}' java version "1.5.0_32" ...
3
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2answers
455 views

how to grep for c:\

I'm using cygwin's grep to find all instances of hardcoded paths on c drive. doing: grep -r "c:\\" . gives grep: trailing backslash Does anybody know how I can do this?
3
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2answers
191 views

Is there a global grep.conf in Unix/Linux?

I would like to make a utility that always enables the --color argument for the grep command in any distribution. Is there a way to do this or do I have to search for a way for each distribution?
3
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3answers
6k views

How can I pass strings with single quotes to grep?

My desired outcome is the following: to recursively search a directory looking for a given string in all found files. The following command is my usual port of call: find ./ | xargs grep -ns 'foobar' ...
3
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4answers
633 views

Find a string (like grep -q) within only a section of a file

I want to write some Bash that can verify that a string exists in a configuration file. I can't change the file format, it belongs to a different application. The file is subdivided into groups named ...
3
votes
3answers
2k views

executing multiple greps in a single find command

I want to use find command to find some files containing multiple patterns at the same time. I tried something like this: find . -name "*.xml" -exec grep -iH keyword1 + && grep -iH ...
3
votes
3answers
318 views

find first line beginning with <keyword> following <other-keyword>

let's present my problem to explain better. I'm using cygwin, the installation is based on a setup.ini with the following format: @ package-name sdesc: "short description, on one line" ...
3
votes
2answers
446 views

Grep log and get text between log delimiters

Is there a way to grep a log and find text between the log entry delimeters? Our log file separates the line entry with characters "-------" So when I search the text word I want all the lines before ...
3
votes
4answers
443 views

extract the characters before () using grep

I need to extract the characters before the character '('. My file structure is: rose(good)ook daisy()no lilly(bad)fine sunflower()nice I need output file as in the form of: rose ...
3
votes
4answers
4k views

extract only the substring after double quotes - grep

I have a file which is as below. <a href="http://firstlink.com" title="title1"> <a href="http://secondlink.com" title="title2"> <a href="http://thirdlink.com" title="title3"> <a ...
3
votes
5answers
192 views

grep device name and look for next value :

I have this output from a find command: abc,10.11.13.14,def,1.2.3.4,geh,6.7.54.23 where abc,def and geh are device names and could be of any length and others are IP address belong to devices. ...
3
votes
3answers
2k views

Average rows with same first column

Given a file with two columns: Id ht 510 69 510 67 510 65 5l0 62 510 59 601 29 601 26 601 21 601 20 I need a way to coalesce all rows with the same ID into one that has an average height. In this ...
3
votes
1answer
173 views

grep for n or more periods on a given line

I want to be able to arbitrarily match lines that contain a lot of periods, like this: $ echo "there's. someone on the wing. some. thing." | grep -stuFF [[:idunno:]]{4,} there's. someone on the wing. ...
3
votes
3answers
396 views

Display lines inbetween text with grep

I know that I can use the -A and -B command for grep to get a lot of what I am looking for however that is not quite what I want. I am looking to parse the httpd.conf file to search for a domain. ...
3
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3answers
1k views

Extracting text from a text file in bash

I have a large text file that is all one line. In the text are several sections that looks like foo=12345 and I need to extract them all as separate lines, ignoring the rest of the file. For ...
3
votes
2answers
1k views

How to search for a string only in textfiles? (recursively)

I can list all the textfiles (by mimetype) in a folder with: find . -type f -print0 | xargs -0 file -i | fgrep -i text | sed 's/:$//g' 2>/dev/null | awk 'BEGIN {FS=": "} {print $1}' Ok. But how ...