---
displayed_sidebar: jsClientSidebar
---

# Interface: UnderlyingSinkWriteCallback<W\>

[internal](../modules/internal-8.md).UnderlyingSinkWriteCallback

## Type parameters

| Name |
| :------ |
| `W` |

## Callable

### UnderlyingSinkWriteCallback

▸ **UnderlyingSinkWriteCallback**(`chunk`, `controller`): `void` \| [`PromiseLike`](internal-8.PromiseLike.md)<`void`\>

#### Parameters

| Name | Type |
| :------ | :------ |
| `chunk` | `W` |
| `controller` | [`WritableStreamDefaultController`](../modules/internal-8.md#writablestreamdefaultcontroller) |

#### Returns

`void` \| [`PromiseLike`](internal-8.PromiseLike.md)<`void`\>

#### Defined in

packages/medusa-js/node_modules/@types/node/stream/web.d.ts:91