### Install getallheaders for PHP < 5.6

Source: https://github.com/ralouphie/getallheaders/blob/develop/README.md

This command installs a specific version of the getallheaders library using Composer for PHP versions older than 5.6. It installs the '^2' version, which is compatible with these older PHP environments.

```bash
composer require ralouphie/getallheaders "^2"
```

--------------------------------

### Install getallheaders for PHP >= 5.6

Source: https://github.com/ralouphie/getallheaders/blob/develop/README.md

This command installs the getallheaders library using Composer for PHP versions 5.6 and later. It ensures you have the latest compatible version of the polyfill.

```bash
composer require ralouphie/getallheaders
```

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