sed Command: Tutorial & Examples

Perform text manipulation and substitution tasks

The sed command is a utility that is used to perform text manipulation and substitution tasks on Linux systems. It is a powerful tool that is often used to edit text files or command output in place, or to filter and transform text in a pipeline.

sed works by reading input line by line, applying a set of rules or commands to each line, and then printing the result. The rules or commands are specified using a simple programming language that is similar to regular expressions.

Here is a simple example of using sed to replace all occurrences of the word "old" with the word "new" in a file:

sed 's/old/new/g' file.txt

You can use the -i flag to edit the file in place, rather than printing the modified file to the terminal:

sed -i 's/old/new/g' file.txt

This will replace all occurrences of the word "old" with the word "new" in the file and save the changes to the file.