grep, sed, and awk

Updated 2026-02-15

grep for search, sed for replace, awk for columns. Common one-liners and regex in shell.

grep

```
grep 'pattern' file
```
Match lines.
```
grep -r 'pattern' dir
```
Recursive.
```
grep -i 'pattern'
```
Ignore case.
```
grep -E 'regex'
```
Extended regex.
```
grep -v 'pattern'
```
Invert match.

sed and awk

sed 's/old/new/g' file (replace). sed -i for in-place (GNU). awk '{ print $1 }' print first column. awk -F',' for CSV. awk '/pattern/ { print }' filter.