---
title: "startSend(_:metadata:handler:)"
framework: network
role: symbol
role_heading: Instance Method
path: "network/networkchannel/startsend(_:metadata:handler:)-5xhjv"
---

# startSend(_:metadata:handler:)

Send partial binary data on a connection.

## Declaration

```swift
func startSend<Content>(_ content: Content, @ProtocolMetadataBuilder metadata builder: () -> [NWProtocolMetadata] = {[]}, handler: ((Content, Bool) async throws -> Void) async throws -> Void) async throws where Content : DataProtocol
```

## Parameters

- `content`: The binary data to send.
- `builder`: A builder for specifying metadata about the content to send.
- `handler`: A handler that will be invoked immediately, and will be passed a closure that should be called repeatedly until all binary data is sent. Intermediate invocations of the send closure must be invoked with isComplete set to false. The last call to the send closure must be invoked with isComplete set to true.

## Discussion

Discussion This may be called before the connection is ready, in which case the send will be enqueued until the connection is ready to send.