What is SED?

- SED is a stream editor and it perform basic text transformations of an input stream (file or input from pipeline)

- SED is capable to perform text pattern substituition and deletion using regular expression

Example of SED editing command substituition: -

UNIX> sed "s/bad/good/g" file.txt > new_file.txt

s/REGEXP/REPLACEMENT/FLAGS – The s command will match the pattern of regular expression (REGEXP) and will replaced it with the REPLACEMENT string. The g command represent the flags “global” where it will perform the search and replace in the entire file.