---
title: "vmnet_interface_start_with_network(_:_:_:_:)"
framework: vmnet
role: symbol
role_heading: Function
platforms: [Mac Catalyst 13.0+, macOS 26.0+]
path: "vmnet/vmnet_interface_start_with_network(_:_:_:_:)"
---

# vmnet_interface_start_with_network(_:_:_:_:)

Starts a new virtual interface instance on a network.

## Declaration

```swift
func vmnet_interface_start_with_network(_ network: vmnet_network_ref, _ interface_desc: xpc_object_t, _ queue: dispatch_queue_t, _ start_block: @escaping vmnet_start_interface_completion_handler_t) -> interface_ref?
```

## Parameters

- `network`: The network that the interface will be added to.
- `interface_desc`: A dictionary describing parameters to use when creating the interface.
- `queue`: The queue on which to schedule the completion handler.
- `start_block`: The block to invoke when the start interface request completes.

## Return Value

Return Value Returns a non-NULL interface handle on success, NULL otherwise.

## Discussion

Discussion Attributes of the virtual interface are specified using the interface_desc dictionary. Namely, vmnet_allocate_mac_address_key vmnet_enable_tso_key vmnet_enable_isolation_key vmnet_enable_checksum_offload_key On success, this call retains the network object.

## See Also

### Starting and stopping interfaces

- [vmnet_start_interface(_:_:_:)](vmnet/vmnet_start_interface(_:_:_:).md)
- [vmnet_interface_set_event_callback(_:_:_:_:)](vmnet/vmnet_interface_set_event_callback(_:_:_:_:).md)
- [vmnet_stop_interface(_:_:_:)](vmnet/vmnet_stop_interface(_:_:_:).md)