EzDevInfo.com

How can I remove the first line of a text file using bash/sed script?

I need to repeatedly remove the first line from a huge text file using a bash script.

Right now I am using sed -i -e "1d" $FILE - but it takes around a minute to do the deletion.

Is there a more efficient way to accomplish this?

Escape a string for a sed replace pattern

In my bash script I have an external (received from user) string, which I should use in sed pattern.

REPLACE="<funny characters here>"
sed "s/KEYWORD/$REPLACE/g"

How can I escape the $REPLACE string so it would be safely accepted by sed as a literal replacement?

NOTE: The KEYWORD is a dumb substring with no matches etc. It is not supplied by user.

Delete empty lines using SED

I am trying to delete empty lines using sed

sed '/^$/d'

but i have no luck with it. for example I have this lines:

xxxxxx


yyyyyy


zzzzzz

and i want it to be like:

xxxxxx
yyyyyy
zzzzzz

what should be the code for this?

Linux command line global search and replace

I'm trying to search and replace a string in all files matched by grep on a linux machine. I've got some pieces of what I want to do, but I'm unsure how best to string them all together.

grep -n 'foo' * will give me output in the form:

[filename]:[line number]:[text]

For each file returned by grep, I'd like replace "foo" with "bar" and write the result back to the file. Is there a good way to do that? Maybe a fancy pipeline?

Awk/Sed: How to do a recursive find/replace of a string?

How to I find and replace every occurrence of:

subdomainA.example.com

with

subdomainB.example.com

in every text file under the /home/www/ directory tree (recursive find/replace).

What are the differences between Perl, Python, AWK and sed? [closed]

just want to know what are the main differences among them? and the power of each language (where it's better to use it).

Edit: it's not "vs." like topic, just information.

Replace comma with newline in sed

I have a file of id's that are comma separated. I'm trying to replace the commas with a new line. I've tried:

sed 's/,/\n/g' file

but it is not working. What am I missing?

sed in-place flag that works both on Mac (BSD) and Linux

Is there an invocation of sed todo in-place editing without backups that works both on Linux and Mac? While the BSD sed shipped with OS X seems to need sed -i '' …, the GNU sed Linux distributions usually come with interprets the quotes as empty input file name (instead of the backup extension), and needs sed -i … instead.

Is there any command line syntax which works with both flavors, so I can use the same script on both systems?

How to output only captured groups with sed

Is there any way to tell sed to output only captured groups? For example given the input:

This is a sample 123 text and some 987 numbers

and pattern:

/([\d]+)/

Could I get only 123 and 987 output in the way formatted by back references?

Delete specific line number(s) from a text file using sed?

I want to delete one or more specific line numbers from a file. How would I do this using sed?

Is there any sed like utility for cmd.exe [closed]

I want to programmatically edit file content using windows command line (cmd.exe). In *nix there is sed for this tasks. Is there any usefull equivalent in windows?

Edit: I am looking for native command line solution.

What is the difference between sed and awk? [closed]

• What is the difference between awk and sed ?
• What kind of application are best use cases for sed and awk tools ?

bash tool to get nth line from a file

Is there a "canonical" way of doing that? I've been using head -n | tail -1 which does the trick, but I've been wondering if there's a bash tool that specifically extracts a line (or a range of lines) from a file.

EDIT: By "canonical" I mean a program whose main function is doing that.

Find and replace with sed in directory and sub directories

I run this command to find and replace all occurrences of 'apple' with 'orange' in all files in root of my site:

find ./ -exec sed -i 's/apple/orange/g' {} \;

but it doesn't go through sub directories.

what is wrong with this command?

Edited: here is some lines of output of find ./ command:

./index.php
./header.php
./fpd
./fpd/font
./fpd/font/desktop.ini
./fpd/font/courier.php
./fpd/font/symbol.php

How can I delete a newline if it is the last character in a file?

I have some files that I'd like to delete the last newline if it is the last character in a file. 'od -c' shows me that the command I run does write the file with a trailing new line:

0013600   n   t  >  \n

I've tried a few tricks with sed but the best I could think of isn't doing the trick:

sed -e '$s/\(.*\)\n$/\1/' abc

Any ideas how to do this?