> For the complete documentation index, see [llms.txt](https://docs.9proxy.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.9proxy.com/developers/sdk/sdk-native-c/functions/setprotocol.md).

# SetProtocol

Configure the SDK connection protocol.

* 0 = Auto
* 1 = Mux
* 2 = Qux

```c
int SetProtocol(int proto)
```

***

## Parameters

* **proto**: Protocol type.

## Return Value

* int – 0 if success.

## Example

```c
// example

SetProtocol(1);

```