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

learn more… | top users | synonyms

3
votes
4answers
2k views

How can I open a file that results from grep?

I often grep a bunch of files to find a line, and then grep returns one result. Rather than copying and pasting the filename into a new command, I'd like to be able to open that one result with an ...
0
votes
2answers
40 views

grep for lines/files that contain exactly X chars

Here's the output of a grep command I ran: [user@localhost] : ~/Documents/challenge $ grep -i -e ".\{32\}" fileA fileB fileA:W0mMhUcRRnG8dcghE4qvk3JA9lGt8nDl fileB:observacion = new Observacion(); ...
3
votes
4answers
92 views

Print alternating lines with conditional

Still struggling with messy logfiles. What I want is to find lines that first matching string X and then string Y. I then want to print them together. The problem is that, sometimes there is X, but no ...
0
votes
2answers
63 views

How to count the number of words of each sentences in a file using shell command?

I have text files like this: Mr.P.K.Baneerjee has visited the site today at 4.30pm The permit tag has been set in the ds busbar Opearation has been performed in presence of control engineer Opeation ...
14
votes
5answers
9k views

Grep: Show all the file up to the match

grep --before-context 5 shows 5 lines before the match. I want to show everything before the match. Doing grep --before-context 99999999 would work but it is not very... professional. How to show ...
1
vote
1answer
43 views

Recursively count occurrences of a word in identically named files in different directories

I've got several different directories that contain different versions of some files. I want to count a symbol in all versions of the same file. Here is an example of the hierarchy. directory ...
3
votes
1answer
156 views

Grep doesn't match carriage return characters

I'm trying to find lines with the carriage return character, but I'm not getting the results I'd expect. I've whittled it down to this proof-of-concept: $ uname -a CYGWIN_NT-6.1 Aodh ...
40
votes
4answers
113k views

How can i count the number of lines of file with common tools in a bash?

I am redirecting grepping-results to a file, and then use cat to show its content on the screen. I want to know how many lines of results I have in my results file and then += it to some counter. ...
3
votes
6answers
435 views

Grep a file on specific field

I have two files, let's say File1: Locus_1 Locus_2 Locus_3 File2: 3 3 Locus_1 Locus_40 etc_849 3 2 Locus_2 Locus_94 * 2 2 Locus_6 Locus_1 * 2 3 Locus_3,Locus_4 ...
0
votes
2answers
70 views

Display filenames with grep

I'm looking for a way to display the filename when using this command: cat *.tcp | grep "tcp" | grep "open" | sort | uniq Is there a way to do it?
1
vote
1answer
61 views

tool in terminal like helm-occur/helm-swoop for terminal?

I don't know whether this is the right place to post this question, but if you are not an Emacs user, I'll explain the basic usage of helm-occur/helm-swoop. I like helm-occur/helm-swoop for Emacs ...
2
votes
2answers
150 views

Grep multiple patterns and print a different number of lines below each of the patterns?

I am trying to find a way to grep/awk multiple patterns and then print a certain number of lines below the first pattern and a certain number of lines below the second pattern. For example .... ...
4
votes
3answers
3k views

GREP / SED or AWK: Print entire paragraph in a file on pattern match [duplicate]

I have a file with hundreds of paragraphs of around 15 lines each. I need to search for a pattern, say Occurance: 1. If this pattern is found in the para, I need to print the entire paragraph. Note ...
0
votes
3answers
55 views

parsing out duplicate barcodes in a separate line

I've got the following data I need to parse out the duplicates from column1 into a separate file, For example, 21288003132541:cr 21288003267289:fr 21288003758683:ph 21288003758683:tag ...
1
vote
4answers
92 views

“head” only printing one line?

I've got a CSV file that's generated by saving as CSV from Excel. If I do "head" (or indeed "grep" or anything else) it only prints the first line: head -n 10 messy.csv 10,15,11,21 But if I open ...
2
votes
3answers
77 views

Split command and arguments, and put into variable in a bash script

I have a script that repeats the same (very long) grep command many times. I want to make the script more readable by cutting the line length, so I tried to put parts of the command into variables. ...
-2
votes
1answer
28 views

exclude names without a comma

How do I exclude names from my list that have no comma and output them to a file? Should I use grep? Example: Charlie Chapman William, Henry Gary, Stevens Mark Twain Harry Potter Smithy, John Mon
7
votes
4answers
572 views

How to grep-inverse-match and exclude “before” and “after” lines

Consider a text file with the following entries: aaa bbb ccc ddd eee fff ggg hhh iii Given a pattern (e.g. fff), I would like to grep the file above to get in the output: all_lines except ...
1
vote
1answer
27 views

Filter screenlog with screen command

Pressing Ctrl+A, H, lets me log output of the screen command. However, the output file is too large. Is it possible to apply a grep-like filter so that I can control what gets logged? For example, I ...
4
votes
1answer
59 views

How can I repair a tar file where stderr got mixed with stdout?

I have a tar file that I'm trying to repair. The problem is that tar's stderr got mixed in with its stdout, so the file looks like this: % head android-1435613730.tar tar: removing leading '/' from ...
28
votes
4answers
37k views

How to search text throughout entire file system?

Assuming that the grep tool should be used, I'd like to search for the text string "800x600" throughout the entire file system. I tried: grep -r 800x600 / but it doesn't work. What I believe my ...
3
votes
2answers
92 views

How do I filter stdout of a program through grep while still controlling the program?

I'm trying to filter the output of the mpv media player, removing a particular line, but when I do so I am unable to control mpv with the keyboard. Here is the command: mpv FILE | grep -v 'Error ...
2
votes
3answers
140 views

Split binary data of fixed byte offset by byte position?

I have binary data which I review by xxd -ps in hex format. I notice that the byte distance is 48300 (=805*60) bytes between two headers where the separator is fafafafa. There is the beginning of ...
-1
votes
1answer
51 views

To sed if with and without conditions correct

I know that I may have the C package #include <stdint.h> in the first 1-30 lines. I would like to add it to lines where no previously if the file contains the word LARGE_INTEGER by GNU tools. ...
1
vote
2answers
188 views

Search for a multiple patterns in specific column in fixed length file and output entire line

I need a command in Unix to look for a pattern in specific columns in a fixed length file and output the entire line to a different file. Example File1 2345abcdef450022677 1234sdfght350022677 ...
2
votes
1answer
27 views

Extract values from block of data

I have the below block of data. Heap after GC invocations=31 (full 3): par new generation total 131008K, used 0K [0x00000000eac00000, 0x00000000f2c00000, 0x00000000f2c00000) eden space ...
1
vote
2answers
61 views

How do i search for certain sections of a file and then extract only relevant information within that section?

So I have a text file that is a server report and has about 1000 lines of information in it. I'm trying to write a script that can search the report for only certain pieces of information I'm looking ...
0
votes
1answer
3k views

grep: match pattern on a particular position

I need to match a pattern with grep, only if it starts at position 16. Let's suppose I want to match the string ' pattern' (starting with space). The following should match bla bla bla bla pattern ...
2
votes
1answer
85 views

Match a number range with grep

I need to find all processes that have in their names a number between 100 and 200 inclusive. I tried ps -ef | grep xclock -bw '[1-2][0-9][0-9]' but that includes 299. How to suppress it and ...
0
votes
1answer
59 views

Delete email addresses in .csv that are listed in a .txt file

I run the following command to keep email addresses listed in emails.txt grep -wFf emails.txt file.csv > newfile.csv But how would I change this command to remove addresses from file.csv that ...
5
votes
1answer
753 views

What's the difference between \b and \< in the grep command

In the man page of grep, I see The symbols \< and \> respectively match the empty string at the beginning and end of a word. The symbol \b matches the empty string at the edge of a ...
3
votes
8answers
3k views

grepping dotfiles with -R correctly?

From time to time I need to find a culprit in an unknown dotfile and instead of trying to figure out which package is to be blamed (e.g. xfce4 or thunar?) and what is their naming convention (.app vs ...
1
vote
1answer
39 views

Obtaining unique lines with matching strings [duplicate]

I have a JSON like text file of records with duplicate ids that look like: {"ID":"93" , "ST":[42,77,51]} {"ID":"21" , "ST":[43,4]} {"ID":"94" , "ST":[65,11,4]} {"ID":"93" , "ST":[42,77,51,29,63]} ...
1
vote
1answer
53 views

Is my understanding correct about egrep -if file1 file2?

I am using KSH, Solaris 5.10. Suppose file1 contains a list of fruits and file2 contains list of fruits & nuts. My understanding about the following command egrep -if file1 file2 is that it ...
0
votes
2answers
60 views

Grep for regex in basename but return wholename

So say I have a list of files in a text file: ... /foo/barfoo /bar/foo/foobar /foobar/bar/foo ... I have a script that will search through this text file and, much like the locate command, I want ...
4
votes
3answers
76 views

Timing of ps piped to grep

So, this isn't a problem as such, just something I'm curious about. I'm using Linux Mint MATE which is branched off Debian. If I do: ps afx | grep abcdefg I get: 16599 pts/3 S+ 0:00 | ...
1
vote
4answers
66 views

Find text in a file and copy it to another file

Is there any command in Linux to find text in a file and if found then copy it in another file? Using sed -i we can find text but how to copy whole line in another file?
-2
votes
1answer
45 views

How to get more than 20 lines of output with grep when searching for a string with spaces [closed]

I am currently using grep like this: grep search_string search_file > output_file Here is an example: grep "ich arbeite" deu.txt > out.txt When used in this way, I only get the last 20 ...
22
votes
11answers
25k views

How can I grep in PDF files?

Is there a way to search pdf files using the power of grep, without converting to text first in Ubuntu?
5
votes
5answers
3k views

Why does grep not work with redirection?

Using the top command with redirection works fine: top > top.log Now I want to use grep to filter a certain line: top | grep "my_program" > top.log But the log file will remain empty. But ...
2
votes
3answers
41 views

grep .* returns results from .bash_history and complains about

I'm new to Linux and so far I've been playing around with some utilities, specifically the grep utility. I decided to create a new file (aptly called 'newfile') with the following content: Lady of ...
0
votes
0answers
20 views

Postgres server start fails - netstat -ant|grep 5432 output explanation?

I'm working on a Ruby on Rails app. Hosting on Heroku with postgres. Tried running "heroku run rake db:migrate" as usual, but getting error "cannot connect,... check if something else is already ...
1
vote
2answers
56 views

How to use multiline as group-separator in grep?

In grep you can use --group-separator to write something in between group matches. This comes handy to make it clear what blocks do we have, especially when using -C X option to get context lines. $ ...
6
votes
3answers
2k views

Suppress 'file truncated' messages when using tail

I'm tailing a log file using tail -f messages.log and this is part of the output: Lorem ipsum dolor sit amet, consectetur adipiscing elit. Fusce eget tellus sit amet odio porttitor rhoncus. Donec ...
2
votes
4answers
128 views

Change text in tag, but only tag is contained within a certain XML block

Using Git Bash, I'm trying to conditionally replace what's in the yrot tag in hundreds of files, but only if it belongs with a part name tag that pertains to wheel. // YES, change <part ...
2
votes
1answer
37 views

Unset all ENV variables matching _PROXY

I'm trying to unset all environment variables that match _PROXY: env | grep -i _proxy | column -t -s '=' | awk '{ print $1 }' | grep -iv 'no_proxy' | xargs -0 -I variable unset variable but it's ...
9
votes
4answers
7k views

How to perform grep on FTP?

I tried searching for similar command in ncftp (actually this is the only terminal ftp client I used) and I didn't find it. What's the way (if possible at all) to use grep command on remote server, ...
5
votes
3answers
372 views

Why does this one-liner fail to produce output? [duplicate]

The following produces nothing in bash: while true ; do upower -d ; sleep 1 ; done | grep percentage | uniq I've discovered that it doesn't matter what the last- or even the second to last- program ...
1
vote
1answer
201 views

“grep: memory exhausted” error on large partition

I was editing a text file with my notes on linux commands when I noticed a big chunk of it was missing (copy without paste, probably). The problem is that I already saved the document. (And this is a ...
1
vote
4answers
560 views

How to use regex to match a pattern which does not have a specific string at the end

How to use a posix bre or a posix ere regex to match a word which does not have bak at the end. I want to do a ls | egrep '<regex>' to find all files which DO NOT have bak at the end of ...