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

Starts a new virtual interface instance on a network.

```
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

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

## Discussion

Attributes of the virtual interface are specified using the `interface_desc` dictionary. Namely,

- [`vmnet_allocate_mac_address_key`](/documentation/vmnet/vmnet_allocate_mac_address_key)
- [`vmnet_enable_tso_key`](/documentation/vmnet/vmnet_enable_tso_key)
- [`vmnet_enable_isolation_key`](/documentation/vmnet/vmnet_enable_isolation_key)
- [`vmnet_enable_checksum_offload_key`](/documentation/vmnet/vmnet_enable_checksum_offload_key)

On success, this call retains the network object.

---

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