> 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/checkportavailable.md).

# CheckPortAvailable

Check whether a port is free (available for use).

```c
int CheckPortAvailable(int port)
```

***

## Parameters

* **port**: Port to check.

## Return Value

* Int: 1 if free, 0 if not free.

## Example

```c
// example

int freep = CheckPortAvailable(1080);

```