sed is a command-line stream editor for filtering and transforming text.

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What does this regex mean?

I was working on the conversion of Unix newline to Windows newline. I tried to unix2dos but it gave me some binary error, so I looked it up and stumbled upon this regex sed 's/$'"/`echo \\\r`/" ...
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3answers
374 views

sed - how to (not) match unmatched brackets

How can I do my operation only on lines that close their brackets? For example I want to change ".is" lines and add a bracket but not for lines with unclosed brackets. so these are changed ...
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1answer
304 views

How can sed add text after existing indent?

I have a sed script that has: sed -i '/ *it.*do/! { /\.should/ { s/\.should/)\.to/ s/\(\S\)/expect(\1/ # ...others The last s adds expect( to the ...
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1answer
154 views

How can I pass in a parameter to sed?

To be more precise - how can I pass in a parameter to a program that then calls sed - how can I 'pass' that parameter along? I have a file 'source_code.sc'. I have a sed script "find_expect": #n ...
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2answers
61 views

Replace “-from” with “this” in the begining of line

I want to replace "-from" with "this" in the begining of line. This should happen when that line has 'R' at the end and line above it has "D" at the end. For example for the block shown below: ...
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3answers
258 views

How to delete a specific line and the following blank line using GNU sed?

I have the following text: Start-Date: 2013-11-11 07:43:49 Commandline: apt-get install --no-install-recommends catfish Start-Date: 2013-11-11 11:27:07 Start-Date: 2013-10-16 22:53:02 ...
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2answers
4k views

sed - how to exclude multiple patterns in the match

I have currently a set of seds that's working well except for one thing. The particular expression I'm having an issue with is: sed -i '/[^}.to]\.to[[:space:]]/ s/\(\S\)/expect(\1/' ...
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1answer
80 views

How to add parens around text

How can I use sed to replace text and also append to end of line for the match in question? I have a sed file which is doing many substitutions. One of them changes ~= to match( using /=\~/ ...
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3answers
237 views

sed - how to do several consecutive substitutions but process file only once?

If I am doing several substitutions which need to be consecutive, e.g. sed -i '/^[[:space:]]*browser.*\.should/s/browser/expect(browser/' t1_spec.rb sed -i ...
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3answers
296 views

how to emulate “replace a b b a” with a sed?

I am trying to emulate a replace command which swaps two characters, with a sed script, but the obvious choice: sed -e 's/a/b/g' -e 's/b/a/g' does no work. Can you point me how to do it correctly? ...
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1answer
85 views

sed - how to replace either space or underscore_word

Currently I have this sed: sed -i '/[^}.to]\.to[[:space:]]/ s/\(\S\)/expect(\1/' ../_spec_seded/"$file" which adds "expect(" at the start of lines that have ".to" (but not "{.to") How can I make ...
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1answer
342 views

grep block of lines

I want to grep every block of lines that has starting line with "CK \" at the end of line and ending line that has "D \" at the end of line, I can use sed/awk/grep etc. So far i have tried following ...
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1answer
2k views

Find all lines between a line matching a pattern and a line matching another pattern

i want to start grepping from the lines that has "CK" at the end of line and stop grepping when the line has "D" at the end. I tried grep "$CK" "$D" file..txt , but it didnt work. Input: kkkkkkkkkkk ...
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2answers
7k views

How to write text into the first line of a file?

I've been looking around sed command to add text into a file in a specific line. This works to add text after line 1: sed '1 a\ But I want to add BEFORE line1. It would be: sed '0 a\ but I get ...
5
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1answer
299 views

Variable in sed

I have a file that contains filenames with absolute path. In the middle of that path, is a variable directory, whenever I hard code the variable part, it works fine, but when I replace it with the ...
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6answers
4k views

Remove lines that do not start with a pattern from a given set of patterns

I have a file that contains data like this: report aaaaaaaa - .. -th bbbbbbbbb -to ccccccccc .. --. Question: I want to remove any line that does not start with following strings : report ...
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1answer
385 views

replace text after match

aaaaaaaaa bbbbbbbbb -th ccccccccc_RD \ DDDDDDDD FFFFFFFF -th GGGGGGG_RD \ using sed/grep/awk etc, In the above text, if a line ends with "RD \" , replace "-th" with "-to" at the ...
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1answer
374 views

Insert a space before the first comma in a csv file

I have a huge CSV file which contains 100000 rows. However, I need to do some processing and so for that I need to have a single space before the first comma. My current data is something like below. ...
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1answer
2k 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 ...
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2answers
2k views

What is the best way to find a list of several strings within a large text file

The short, general question is: In Unix/Linux, what is the best way to find a list of several (about 150) strings within a large text file? I am asking this to all Unix/Linux experts as a general ...
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1answer
360 views

Search low values in mainframe files

I am working with mainframe files and it seems that the low values (x'00') exists in the records in the file which throws off my import for fixed block. Does anyone know how to eliminate those ...
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2answers
496 views

iterate through files ('for file in…) and also include sub directories?

I am using sed to do a bunch of changes to files. I think the question is relevant for any operation that want to iterate through files that match a pattern and include subdirectories both in the ...
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1answer
200 views

best programming language for I/O intensive tasks [closed]

I need to process "big data" (nearly 1TB which can be partitioned into smaller chunks). Consider several programming languages (Java, Python, C++, Perl) and other scripting options (Perl, awk, sed, ...
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1answer
253 views

Matching Five Columns in two Files using Awk

I have two Input files. File1: s2/80 20 . A T 86 F=5;U=4 s2/20 10 . G T 90 F=5;U=4 s2/90 60 . C G 30 ...
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3answers
96 views

Using sed (?) to extract one instance of a string that is repeated in the original string

INPUT: <a href=FII/FOO./>FOO</a> OUTPUT: FOO Q: how can I replace the INPUT with the OUTPUT? The FII and "./>" is CONSTANT. The FOO could vary to any english letter and "-" and "." ...
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1answer
245 views

Reverse a line in sed?

echo 1234 | sed ' /\n/ !G s/\(.\)\(.*\n\)/&\2\1/ //D s/.// ' I'm unable to comprehend the above sed code. my understanding is: PATTERN SPACE=1234 first ...
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2answers
190 views

Replace a pattern which ends at newline with the same pattern without the newline

I have a javascript file with two new lines after a particular word "[FACT]", I want to replace it with one newline. I need to do it in bash script. Normally, I would have used sed but it turns out ...
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1answer
113 views

Is strace a suitable tool for finding out where a program wrote to the filesystem?

I'd like to determine where a certain app (as an example, surf) writes to the filesystem in order to make sure it leaves no traces. Without a dedicated sandboxing system this probably isn't easy, but ...
5
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1answer
9k views

Using sed to extract text between 2 tags

I have a .xml file and I'm trying to do a "groupinstall" on a RHEL6 machine as there are several hundred libraries in that .xml file... (close to 16 000 lines). I'm therefore trying to extract the ...
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4answers
70 views

How to make 1:52 to 01:52 with eg.: sed?

INPUT: a|2013.06.13. 13:22|xx b|2013.06.13. 1:52 |xx c|2013.06.13. 2:26 |xx OUTPUT: a|2013.06.13. 13:22|xx b|2013.06.13. 01:52 |xx c|2013.06.13. 02:26 |xx How can I make the 1:52 to 01:52 in ...
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3answers
1k views

using sed to replace pattern with hash values

I want to search the file and replace specific pattern with its hash (SHA1) values. For example, let file.txt has the following content: one S56G one two three four five V67X six and I want to ...
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5answers
2k views

extract fields from “tail -f” of a syslog stream

Example line from syslog file: Aug 1 10:25:50 10.10.10.1 id=firewall sn=XXXX time="2012-08-01 14:35:18 UTC" fw=x.x.x.x pri=6 c=1024 m=537 msg="Connection Closed" f=11 n=195273698 ...
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4answers
571 views

How to Prefix a column values with an apostrophe ( ' )?

I have a CSV file with multiple columns and 1000's of records, I need to prefix all the values of one of the columns (lets say 2nd column) with an apostrophe ' except in the first line or header line, ...
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0answers
26 views

Variable Substitution in sed [duplicate]

I have this script and I need to count the lines inside a file, then pass the number of lines counted to a for loop so that I can get the contents of each line and put it in a variable. My question ...
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3answers
351 views

Reversing the value key pairs of array using sed or pattern replacement or brace expansion?

#!/bin/bash arr=(a b c d) declare -A brr for i in ${!arr[@]} do brr[${arr[$i]}]=$i done echo ${brr[@]} #0 1 2 3 Is there any way to reverse the values and key pairs ...
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4answers
7k views

How exactly do I create a sed script and use it to edit a file? [duplicate]

I know how to edit a file using sed one step at a time, but how would I create an actual sed script and then use it on the file to do the same things that the individual sed commands would do? For ...
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3answers
892 views

Deleting Lines if there is a dot in the 5th Column

I have a file and I want to remove all the line if it has a dot in the 5th Column. Input File: sc2/80 20 . A C 80 PASS N=2 F=5;U=4 sc2/60 ...
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2answers
233 views

How would I use sed to detect a certain amount of numbers before it inserts a character? ###-###-####

I need to format phone numbers in a text file. They appear as (example) 8014516912 How would I format it so that I can insert a - after the first 3 numbers, and then another - after another 3 ...
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1answer
2k views

How would I use sed to insert a character at a certain character position on only ONE line?

I am aware that this will do what I want on all lines: sed 's/^\(.\{4\}\)/\1-/' textFile But how would I enter a - after the 4th character slot on ONLY the 5th line? Or even better, on a range of ...
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2answers
10k views

Removing text between two specific strings

I have a file as below: mime PI Name: ISHO SUCCESS RATE RT, Value: 95.663826 scr PI Name: RRC Access Failures due to UU, Value: 0.13394141 prog PI Name: RRC Access Failures due to UU, Value: ...
2
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1answer
197 views

How to extract single value from single line tuples?

I have a dump file of a database in the following form ('value1','value2',value3','value4'),('value1','value2',value3','value4'),... I want first to have each tuple in a single line and next i ...
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1answer
739 views

Efficient way to print lines from a massive file using awk, sed, or something else? [duplicate]

If I had a plain-text file containing 8 million lines and I want to print out lines 4,000,010 to 4,000,000 to the screen, which would be more efficient: awk or sed? There is no pattern to the text, ...
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1answer
86 views

Can i use & variable of sed for doing operation inside $()? [duplicate]

I am not sure whether the below statement can be done placing & inside $() so that each time & is replaced by 1,2,3,4 and 1 is added to it. echo 1 2 3 4 | tr ' ' '\n' | sed "s/.*/$(echo expr ...
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2answers
1k views

sed: match two lines

I have a text file, where records are split on two lines. I would like to put them on one line. The records look something like this: 2013-07-29 apt-get install git 2013-07-29 apt-get install rsync ...
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4answers
64 views

cut+sed function joined

Input dir/foo Output dir./ so I need: echo 'dir/foo' | MAGIC Q: What is MAGIC? (something like a cut+sed joined:D)
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3answers
2k views

Count the number of rows in each column of a text file

I have a text file with the following format: 5 3 1 2 3 4 ..... ..... i.e. space separated 3 columns of numbers/ However, some of the rows may be like: 2 3 1 So, I want to detect if the text file has ...
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1answer
373 views

How to use awk or sed to convert csv diffs into more readable format

Can anyone give me the example of how to use awk or sed (not sure which one, as I haven't use either of these much, as I have mostly been using grep and cut to work with csv data) to convert ...
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3answers
2k views

Printing match groups with grep

I have the following grep: grep -Po 'href="(http://.*)">Transcript.* - ([0-9]*)\. (.*)</a>' I would like to print out the match groups. Is there a way to do this without Perl/Python? I ...
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5answers
23k views

Multiline pattern match using sed, awk or grep

Is it possible to do a multiline pattern match using sed, awk or grep? Take for example, I would like to get all the lines between { and } So it should be able to match 1. {} 2. {.....} 3. ...
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1answer
4k views

How to assign result of sed to variable

Below is a complete copy of a demo I'm using to to figure out to get the sed command to get rid of the spaces in a persons name, and compress it down to not have spaces. Once this is done, I want to ...