SED - Stream Editor

sed [-En] command [file...]
sed [-En] [-e command] [-f command_file] [-i [extension]] [file...]

Grammar

command : [address[,address]]function[arguments]

address : [0-9]... || $ || /regex/

function : todo

-E : used extended regular expressions

-n : suppress stdout (by default each line of input is streams to stdout after applying functions)

-i : edit the input file in place. optionally add an extension if you want to back up the original file.

Examples

Notation	Effect
8d	Delete 8th line of input.
/^$/d	Delete all blank lines.
1,/^$/d	Delete from beginning of input up to, and including first blank line.
/Jones/p	Print only lines containing "Jones" (with -n option).
s/Windows/Linux/	Substitute "Linux" for first instance of "Windows" found in each input line.
s/BSOD/stability/g	Substitute "stability" for every instance of "BSOD" found in each input line.
s/ *$//	Delete all spaces at the end of every line.
s/00*/0/g	Compress all consecutive sequences of zeroes into a single zero.
`echo "Working on it."	sed -e q'1i How far are you along?'`	Prints "How far are you along?" as first line, "Working on it" as second.
5i 'Linux is great.' file.txt	Inserts 'Linux is great.' at line 5 of the file file.txt.
/GUI/d	Delete all lines containing "GUI".
s/GUI//g	Delete all instances of "GUI", leaving the remainder of each line intact.