# MIDIGetDriverIORunLoop() Returns the server’s driver I/O thread. ``` func MIDIGetDriverIORunLoop() -> Unmanaged ``` ## Return Value The of the server’s driver I/O thread. ## Discussion Drivers typically need to receive asynchronous I/O completion callbacks on a high-priority thread. So that the system can efficiently manage resources, the MIDI server provides a thread which drivers may use. This is a realtime-priority thread that drivers shouldn’t use for anything other than I/O. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)