<!--
{
  "availability" : [
    "iOS: -",
    "iPadOS: -",
    "macCatalyst: -",
    "macOS: -",
    "tvOS: -",
    "visionOS: -",
    "watchOS: -"
  ],
  "documentType" : "symbol",
  "framework" : "Dispatch",
  "identifier" : "/documentation/Dispatch/DispatchSourceProtocol/setRegistrationHandler(qos:flags:handler:)",
  "metadataVersion" : "0.1.0",
  "role" : "Instance Method",
  "symbol" : {
    "kind" : "Instance Method",
    "modules" : [
      "Dispatch"
    ],
    "preciseIdentifier" : "s:So18OS_dispatch_sourceP8DispatchE22setRegistrationHandler3qos5flags7handleryAC0D3QoSV_AC0D13WorkItemFlagsVyyXLSgtF"
  },
  "title" : "setRegistrationHandler(qos:flags:handler:)"
}
-->

# setRegistrationHandler(qos:flags:handler:)

```
func setRegistrationHandler(qos: DispatchQoS = .unspecified, flags: DispatchWorkItemFlags = [], handler: Self.DispatchSourceHandler?)
```

---

Copyright &copy; 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)