nushell/docs/commands/extern.md

---
title: extern
layout: command
version: 0.59.1
---

Define a signature for an external command

## Signature

```> extern (def_name) (params)```

## Parameters

 -  `def_name`: definition name
 -  `params`: parameters

## Examples

Write a signature for an external command
```shell
> extern echo [text: string]
```
Auto-generate markdown command docs (#4451) * Finish updating * a couple improvements * Update renames * cleanup examples 2022-02-14 03:22:51 +01:00			`---`
			`title: extern`
			`layout: command`
fix typo, update some examples and regenerate docs (#4718) 2022-03-04 13:10:09 +01:00			`version: 0.59.1`
Auto-generate markdown command docs (#4451) * Finish updating * a couple improvements * Update renames * cleanup examples 2022-02-14 03:22:51 +01:00			`---`

			`Define a signature for an external command`

			`## Signature`

			```> extern (def_name) (params)```

			`## Parameters`

			- `def_name`: definition name
			- `params`: parameters
Fix some examples and regenerate docs, should fix: #4455 (#4639) 2022-02-25 14:14:15 +01:00
			`## Examples`

			`Write a signature for an external command`
			```shell
			`> extern echo [text: string]`
			```