# Getting the line number of the nth match

If we're aiming to find the line number of the nth match, we might think to use `grep` and parse it's output.

Take this markdown document for example, where we want to find the line number of the second occurrence of `---`:

*input.md*

```
---
title: some frontmatter
--- <-- We want the line number of this line

# Some content
```

```bash
grep '^---$' -m 2 -n input.md | tail -1 | cut -d ":" -f 1
```

This gets the job done, but it invokes a number of subshells, reducing performance. An alternative using `awk` may be less I/O intensive:

```bash
awk '/^---$/ && (++c == 2) { print NR; exit }' input.md
```

[Source](https://stackoverflow.com/questions/57044203/how-to-get-the-line-number-of-nth-match#comment100617725_57044437)