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kIOFWMessageServiceIsRequestingClose
Treat FireWire service close-request message as a contract result, not as justification for resetting unrelated state. This IOKit message notifies a client that the FireWire service is requesting closure; it is a lifecycle notification, not a transfer error.
First returning layer
IOKit results, internal tokens, and service messages cross user space, kernel services, and hardware families in an investigation of FireWire service close-request message. Their integer representation does not make their control-flow roles interchangeable for the FireWire service close-request message case.
IOKit return values, internal tokens, and service messages share an integer representation but not the same control-flow meaning in an investigation of FireWire service close-request message. Determine whether the API returns the value or delivers it as a message before treating it as failure for the FireWire service close-request message case. Keep the numeric value, declared return type, and first returning operation together with kIOFWMessageServiceIsRequestingClose; the same integer can belong to a different status namespace in another API.
Evidence map
| Capture | Diagnostic value |
|---|---|
| Service registry entry, client connection, message timestamp, open count, and outstanding requests. | Identifies the concrete object and operation associated with FireWire service close-request message. |
| Numeric IOReturn/message value decoded with the matching SDK header when diagnosing FireWire service close-request message. | Separates argument or lifecycle state from the provider beneath FireWire service close-request message. |
| Registry generation and first provider/client event before the result in an investigation of FireWire service close-request message. | Creates a stable before-and-after comparison for FireWire service close-request message. |
| Known-good device or service state on the same macOS/driver build for the FireWire service close-request message case. | Shows whether FireWire service close-request message is the first result or a translated summary. |
For FireWire service close-request message, preserve known-good device or service state on the same macOS/driver build while evaluating FireWire service close-request message before reinstalling, rebooting, clearing state, or substituting another device or provider. A success observed only after such a change is useful comparison data for FireWire service close-request message, but it does not identify the original cause.
Change one condition at a time
- Acknowledge/close a disposable client after receiving the message. Repeat the original supported operation so the check remains relevant to FireWire service close-request message.
- Change one topology or lifecycle condition while keeping the request payload fixed when diagnosing FireWire service close-request message. Keep unrelated inputs fixed so the change remains attributable to FireWire service close-request message.
- Verify cleanup and object lifetime after the controlled operation in an investigation of FireWire service close-request message. Record the first returned status and any state transition observed during FireWire service close-request message.
Decision points
| Observed comparison | Next conclusion to test |
|---|---|
| The first control changes the result | Concentrate on the variable isolated by this check: Acknowledge/close a disposable client after receiving the message. |
| The second comparison for FireWire service close-request message reproduces the same first status | Preserve lower-layer provider, driver, service, or runtime evidence before editing application data. The second controlled check was: Change one topology or lifecycle condition while keeping the request payload fixed when diagnosing FireWire service close-request message. |
| A different status replaces FireWire service close-request message after the bounded change | The operation moved to another boundary after the third controlled check. That check was: Verify cleanup and object lifetime after the controlled operation for the FireWire service close-request message case. Retain both results and interpret the replacement through its own API contract for FireWire service close-request message. |
Repair and regression test
Targeted correction. Quiesce I/O, release user-client resources, and close through the documented message handler. For FireWire service close-request message, modify only the object, argument, policy, provider, or lifecycle state identified by the collected evidence.
Acceptance criterion. The client closes without leaked opens and later reopen follows a fresh service generation. Re-run the original operation that produced FireWire service close-request message under its original identity and supported configuration, then keep one negative control that still produces the expected neighboring outcome.
Technical references
These owner-maintained or standards-based sources define the namespace and subsystem contract needed to verify kIOFWMessageServiceIsRequestingClose on the deployed platform version.
- Apple XNU: IOReturn definitions — defines the status namespace used for FireWire service close-request message.
- Apple: IOKit documentation — documents the API or lifecycle boundary behind FireWire service close-request message.
- Apple OSS: XNU source — provides ABI, implementation, or protocol context for FireWire service close-request message.
- Apple XNU: FireWire family common definitions — supports the portability and verification limits for FireWire service close-request message.
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