sed 🖊️
Edits streams by applying commonly used modifications.
Add a new line a & i
cat some-file.txt | sed '3a This is a new line after the 3rd line'
cat some-file.txt | sed '3i This is a new line before the 3rd line'
Append a new line to the end $a
cat some-file.txt | sed '$a Now, this is the last line'
Prepend a new line to the beginning 1i
cat some-file.txt | sed '1i Now, this is the first line'
Replace one or more lines c
cat some-file.txt | sed '1-3c BOOM'
Replaces lines 1 through 3, with 'BOOM'.
Delete one or more lines d
cat some-file.txt | sed '1-3d'
Deletes lines 1 through 3.
Top comments (2)
These were some uses of sed I wasn't aware of, thanks. Still, the true power of sed must be acknowledged to be its replacement capabilities using regular expressions. For example, search and replace within a directory:
find . -name \*.js -exec cat {} | sed -e 's#replaceme#replacement#g' > output.txtThat's right. I'll cover some use cases of string/pattern substitution in Part 2.