# Allowed Bindings

The extension limits the bindings that are generated by `bindgen` to a subset of the original bindings.
Those bindings are defined in the `allowed_bindings.rs` file.

Should you need to add more bindings, you can do so by defining them as a comma-separated list in the `EXT_PHP_RS_ALLOWED_BINDINGS` environment variable.

This can be configured in your `.cargo/config.toml` file:

```toml
[env]
EXT_PHP_RS_ALLOWED_BINDINGS = "php_foo,php_bar"
```

Your bindings should now appear in the `ext_php_rs::ffi` module.

<div class="warning">
Pay attention to the PHP version

Be aware, that bindings that do not exist in the PHP version you are targeting will not be available.

Some bindings may also change between PHP versions, so make sure to test your extension with all PHP versions you are targeting.
</div>

## Contributing

If you think that a binding should be added to the allowed bindings, please open an issue or a pull request on the [GitHub repository](https://github.com/extphprs/ext-php-rs) so that everyone can benefit from it.
