---
title: WritePipeAsyncTO
framework: IOKit
role: symbol
role_heading: Instance Property
platforms: [Mac Catalyst 18.4+, macOS 10.14+]
path: iokit/iousbinterfaceinterface942/2977257-writepipeasyncto
---

# WritePipeAsyncTO

## Declaration

```occ
IOReturn (*WritePipeAsyncTO)(void *self, UInt8 pipeRef, void *buf, UInt32 size, UInt32 noDataTimeout, UInt32 completionTimeout, IOAsyncCallback1 callback, void *refcon);
```