> ## Documentation Index
> Fetch the complete documentation index at: https://docs.microsandbox.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# VSock

> Rust SDK - VSock API reference

Expose a host Unix socket or local Windows named pipe to a sandbox over virtio-vsock. See [VSock](/networking/host-sockets) for guest connection details, platform support, and security considerations.

<Note>VSock routes are local-only and unavailable with the multi-tenant deployment profile.</Note>

## Typical flow

```rust theme={null}
use microsandbox::Sandbox;

let sandbox = Sandbox::builder("worker")
    .image("alpine")
    .vsock("/run/host-api.sock", 5000)
    .create()
    .await?;
```

## SandboxBuilder

### vsock()

```rust theme={null}
fn vsock(self, host_path: impl AsRef<Path>, port: u32) -> Self
```

Expose a host Unix stream socket or local Windows named pipe on host CID `2` at `port`.

### vsock\_dgram()

```rust theme={null}
fn vsock_dgram(self, host_path: impl AsRef<Path>, port: u32) -> Self
```

Expose a host Unix datagram socket while preserving datagram boundaries. Datagram routes are unavailable on Windows.

### vsock\_route()

```rust theme={null}
fn vsock_route(self, route: VsockRouteSpec) -> Self
```

Add a fully specified route using [`VsockRouteSpec`](#vsockroutespec).

## VsockRouteSpec

Import path: `microsandbox::sandbox::VsockRouteSpec`.

| Field         | Type              | Description                                           |
| ------------- | ----------------- | ----------------------------------------------------- |
| `host_socket` | `PathBuf`         | Existing Unix socket or local Windows named-pipe path |
| `port`        | `u32`             | Guest-facing port on host CID `2`                     |
| `socket_type` | `VsockSocketType` | `Stream` or `Dgram` message semantics                 |

Host paths must be absolute, and each socket type and port pair must be unique.

## VsockSocketType

Import path: `microsandbox::sandbox::VsockSocketType`.

| Variant  | Description                                             |
| -------- | ------------------------------------------------------- |
| `Stream` | Reliable, ordered byte stream; the default              |
| `Dgram`  | Best-effort messages with preserved datagram boundaries |