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

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6
votes
3answers
754 views

emulate tail with sed

I have a mini-system with only limited number of binaries (bash,cp,cat,sed, ...). I don't have tail command, and I am wondering if I could emulate tail functionality with sed cat foo.txt | tail -n 10 ...
6
votes
2answers
529 views

How to report “sed” in-place changes

When using sed to replace strings in-place, is there a way to make it report the changes it does (without relying on a diff of old and new files)? For instance, how can I change the command line ...
6
votes
4answers
14k views

Text between two tags

I wanna retrieve whatever is between these two tags – <tr> </tr> – from an html doc. Now I don't have any specific html requirements that would warrant for an html parser. I just plain ...
6
votes
7answers
11k views

How to print all lines after a match up to the end of the file?

Input file1 is: dog 123 4335 cat 13123 23424 deer 2131 213132 bear 2313 21313 I give the match the pattern from in other file ( like dog 123 4335 from file2). I match the pattern of the line ...
6
votes
1answer
167 views

Confusion about sed and '>'

The following command works fine: sed s/input/raw_input/ p.py >p2.py && mv p2.py p.py However, the following command turns p.py into an empty file: sed s/input/raw_input/ p.py >p.py ...
6
votes
3answers
226 views

Locate postion then make a change using sed

This script uses sed to change all "" to "new stuff". How would one change just the "" after the yyy: using sed or anything else? cat >sample.txt <<EOF xxx: "" yyy: "" } EOF sed ...
6
votes
6answers
1k views

sed - remove the very last occurance of a string (a comma) in a file?

I have a very large csv file. How would you remove the very last , with sed (or similar) ? ... [11911,0,"BUILDER","2014-10-15","BUILDER",0,0], [11912,0,"BUILDER","2014-10-15","BUILDER",0,0], ...
6
votes
4answers
18k views

Can sed replace new line characters?

Is there an issue with sed and new line character? I have a file test.txt with the following contents aaaaa bbbbb ccccc ddddd The following does not work: sed -r -i 's/\n/,/g' test.txt ...
6
votes
4answers
4k views

Why is sed giving me an error about an unterminated `s'?

I have a set of sed replacements in a bash script and am getting an error about an unterminated `s' command. Here's what the sed line looks like: sed -n -e "s/TMPFOO1/$FOO1/" -e "s/TMPFOO2/$FOO2/" ...
6
votes
2answers
3k views

Replacing missing value blank space with zero

I have input.txt tab-delimited text file around 30K lines, I would like to check each row (s1..s30K lines) for missing value (i.e blank space) and fill the missing value with zero value.See out.txt ...
6
votes
3answers
3k views

How to embed a shell command into a sed expression?

I have a text file with the following format: keyword value keyword value ... Where keyword is a single word and value is everything else until the end of line. I want to read the file from a shell ...
6
votes
4answers
4k views

Concatenate lines by first column (AWK or SED)

How can I use AWK in the following situation? I want to concatenate lines that start with the same column. Only the first column is kept after the join (in this case aaa, www, hhh). The file may be ...
6
votes
2answers
715 views

How would I sort these directory names numerically?

I'm aware that I can somehow sort this output numerically (so cpu1/ follows cpu0/) ... I could probably get something to work eventually by splitting up the string various ways with awk, but is there ...
6
votes
1answer
1k views

Why isn't sed greedy in this simple case?

$echo "foo 65 bar" | sed -n -e 's/.*\([0-9]\+\).*/\1/p' 5 Why is the output not 65? Shouldn't sed greedily match the [0-9]\+ part? How do I tell sed to match all of 65?
6
votes
5answers
275 views

Remove backslash + newline sequences

We are having a file in Linux which contains one line per record, but problem comes when the line contains some new line characters. In this case, the backslash is appended at the end of line and the ...
6
votes
4answers
247 views

How to insert lines with numbers from X to Y into another file after line Z?

I created two files: echo -e "1\n2\n3\n4\n5" > 123.txt echo -e "a\nb\nc\nd\ne" > abc.txt I want to get the file 123.txt with the following contents: 1 2 3 b c d 4 5 So in other words ...
6
votes
1answer
3k views

Removing leading zeros from DATE

I made an alias of the date command to display date in the following format: 2013.06.14.12.10.02 using this command: alias date = date +"%Y.%m.%d.%H.%M.%S" Everything works great, except I ...
6
votes
1answer
12k views

Only return the matched string in sed [duplicate]

Possible Duplicate: Extracting a regex matched with 'sed' without printing the surrounding characters How do I make this only print test: echo "atestb" | sed -n 's/\(test\)/\1/p'
6
votes
2answers
455 views

what is the meaning of this sed command: `;/@/{h;s/test/next/g;x;G}`?

sed -e 's/72;/72, next_val = 0x11111111;/;/@/{h;s/test/next/g;x;G}' fmt_vuln.c > fmt_vuln2.c could you tell me about what is the meaning of ;/@/{h;s/test/next/g;x;G}?
6
votes
2answers
2k views

Cleanly swap all occurences of two strings using sed

Suppose I have a file that contains multiple occurrences of both StringA and StringB. I want to replace all occurrences of StringA with StringB, and (simultaneously) all occurrences of StringB with ...
6
votes
2answers
2k views

Remove unknown unicode character from textfiles - sed, other bash/shell methods

I need to search and replace all occurences of an unknown character in some files having the same name. Opening such files with vi, I read <91> code for that character. Opening them with nano, I ...
6
votes
2answers
211 views

Regex `/pattern/g` and ed `:g/pattern/`: which came first, and why `g`?

The g option (e.g. s/pattern/replacement/g) for many tools that use regex-style pattern matching and the :g command in ed, ex, vi, and vim have pretty similar usage and meaning: match the given regex ...
6
votes
1answer
720 views

grep: display filename once, then display context with line numbers

Our source code has error codes scattered throughout. Finding them is easy with grep, but I'd like a bash function find_code that I can execute (eg. find_code ####) which will provide output along ...
6
votes
3answers
139 views

Sed alternative for search and replace on very long lines

I have files that were generated by a program that did not put newlines at the end of records. I want to put newlines between the records, and I can do so with a simple sed script: sed -e ...
6
votes
3answers
1k views

Multi-line replace

I spent ages trying to figure this out. As it happens, I don't need to do it any more; I found another way. But for the sake of my sanity, I'd like to know the answer anyway. It's quite easy to use ...
6
votes
2answers
123 views

How come sed is so fast?

I thought about whether this question is suitable for SE or not, I hope you agree it is. Some time ago I asked on SE how to find text in files and leave the file with only the matching lines that ...
5
votes
8answers
6k views

Can sed remove 'double' newline characters?

I have a document with a lot of empty lines. How can I remove them when there are 2 or more together. I tried sed "s/\n\n//" file but it didn't work. No error.
5
votes
6answers
9k views

How to use the sed command to only show the first column and last column in a text file

I need some help to figure out how to use the sed command to only show the first column and last column in a text file. Here is what I have so far for column 1: cat logfile | sed 's/\|/ /'|awk ...
5
votes
4answers
1k views

How to append end of every line with the line itself

This is in file.txt: redcar bluecar greencar Im looking for ways to make it become: redcar redcar bluecar bluecar greencar greencar I've tried many ways using sed with no luck
5
votes
5answers
765 views

Sed: extending a string of numbers to a certain number of digits by padding with zeros

I'm currently trying to modify an echoed string of alphanumeric characters by piping it to sed. The area I'm interested in modifying is a block of numbers, which I would like to make 8 characters long ...
5
votes
4answers
367 views

Remove next-to-last extension in a file name

Suppose a folder with many files with bad extensions,for example Song1.avi.mp3 Song2.avi.mp3 Song32.web.mp3 Song23.mp4.mp3 Song2a.mp9.mp3 I want to remove only the second field (web, avi, mp4). I ...
5
votes
4answers
482 views

Reduce the over use of files in text processing

Currently, I have a file (Results.txt) which has 27k rows. The file content is as below. 45008657 | A. | | Long | 0 49210987 | A. | ...
5
votes
3answers
575 views

Why does sed act differently depending on the output file?

If I run: cat messages.txt | sed -e 's/a/a/g' > messages.txt on one large file (2500+ lines) I find that the resulting file will only have about 900 lines after the command in cygwin and will ...
5
votes
7answers
949 views

Replace a character except last x occurences

I have a file that has a bunch of hostnames correlated with IPs that looks like this: x-cluster-front-1 192.168.1.2 x-cluster-front-2 192.158.1.10 y-cluster-back-1 10.1.11.99 y-cluster-back-2 ...
5
votes
3answers
676 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 ...
5
votes
4answers
802 views

Replace a string containing newline characters

With the bash shell, in a file with rows like the following ones first "line" <second>line and so on I would like to replace one or more occurrences of "line"\n<second> with other ...
5
votes
2answers
313 views

How is the inplace modification of a file being done?

What does the "inplace" modification of a file e.g. via sed -i or perl -i mean? My question is about how this inplace modification is done. Is the file copied the modification is done in the copy and ...
5
votes
3answers
586 views

Is it possible to match multiple specific line numbers (not range) with sed?

Consider: echo -e "a\nb\nc\nd\ne\nf\ng\nh" | sed '3,5a test' This will match lines 3, 4 and 5. But I am trying to match only lines 3 and 5 (not 4). And append 'test' after them.
5
votes
4answers
390 views

reverse order of paragraphs in file

I have a file containing text in paragraphs (lines with text separated by one or more empty lines). I would like to reverse the order of paragraphs (i.e. last paragraph will become the first, ...), ...
5
votes
4answers
578 views

sed how to substitute when string has “http://” in it?

I have a file xx that has the following contents: @base_url = "http://dmstaffing-stage.herokuapp.com/" I want to use sed to eliminate this line (replace with nothing). I have used this sed ...
5
votes
2answers
5k views

How to replace a left parenthesis with sed?

I have to replace ( with some character in my file, and I can't do it. \( is used for grouping in sed and when I used \\( with sed, it treated it as \( character not as just (. It seems like a tricky ...
5
votes
4answers
231 views

How could I simplify this command to only use awk?

awk '/user/ {print $1 }' /etc/userdomains | sed 's/://' the format of /etc/userdomains is domain.tld: user otherdomain.tld: otheruser
5
votes
5answers
318 views

How to run a command only if sed replace strings

I want to enable multiverse repository in Ubuntu by a command line. sed -i "/^# deb.*multiverse/ s/^# //" /etc/apt/sources.list && apt-get update This command will run apt-get update every ...
5
votes
2answers
234 views

sed + how to delete the second character “.” from the line

how to delete the second character "." from the line what I have is this ( but its remove the first "." from output uname -r | sed s'/\./ /' 2 6.18-164.2.1.el5PAE while I need the following ...
5
votes
2answers
511 views

Does `sed` exist in all *nixes?

My application will be running on all versions of Unix-based OS, say, Linux, MacOS, HP-UX, Sun Solaris , OSX, etc. I'm using the following sed command in a common place to delete the string matched ...
5
votes
4answers
377 views

Is there a difference between read, head -1, and sed 1q?

The following commands seem to be roughly equivalent: read varname varname=$(head -1) varname=$(sed 1q) One difference is that read is a shell builtin while head and sed aren't. Besides that, is ...
5
votes
4answers
422 views

sed ranges aren't always able to match only one line

Consider the following range: 1,/pattern/. If pattern matches on the first line, the range matches for the whole file: $ cat 1.sh #!/usr/bin/env bash set -eu seq 1 4 | sed -rn '1,/'"$1"'/p' $ ./1.sh ...
5
votes
3answers
3k views

How can sed output be formatted like printf's formatted printing?

Can sed replace text with a string formatted like printf's formatted printing? The following sed command replaces a line starting with the current value of "$domain" with several values specified in ...
5
votes
1answer
2k views

Replacing multiple lines in sed or awk [closed]

I'm trying to use sed or awk to replace 5 lines in a smb file but I just don't have any idea how to deal with the newlines.
5
votes
4answers
1k views

sed behaves different on FreeBSD and on Linux?

I use both Linux and FreeBSD (specifically, I use Debian Linux and PC-BSD), and I found something weird about sed. I frequently need to convert "tab separated values" files to "comma separated ...