---
layout: docs
title: setShebangLine
id: class.Facebook.HackCodegen.CodegenFile.setShebangLine
docid: class.Facebook.HackCodegen.CodegenFile.setShebangLine
permalink: /docs/reference/class.Facebook.HackCodegen.CodegenFile.setShebangLine/
---
# Facebook\\HackCodegen\\CodegenFile::setShebangLine()




Useful when creating scripts




``` Hack
public function setShebangLine(
  string $shebang,
): this;
```




You probably want:
setShebangLine('#!/usr/bin/env hhvm')




## Parameters




- ` string $shebang `




## Returns




+ ` this `