FB9093710: fn key is ignored when posting a CGEvent

[godbout]

• Date: 2021-05-01
• Resolution: Open
• Area: Core Graphics API
• OS: oops
• Type: Incorrect/Unexpected Behavior

Description

when posting an CGEvent with the fn key enabled, the posted event doesn't act like the fn key was pressed. in the below case, i'm supposed to post a forward delete key combination, but it does a backward delete instead. the fn is present in the CGEvent, but it is still not applied. all the other masks work well, so the rest of the code shouldn't be the issue.

to test, you can use the code below:

var eventTapCallback: CGEventTapCallBack = { proxy, _, event, _ in              
        let fnDeleteDown = CGEvent(
            keyboardEventSource: nil,
            virtualKey: 51,
            keyDown: true
        )
        
        fnDeleteDown?.flags = [.maskSecondaryFn]
        fnDeleteDown?.tapPostEvent(proxy)
        
        return nil
    }

[godbout]

answer from Apple:

After reviewing your feedback, we have some additional information for you, or some additional information, or action is necessary for this issue: 

Please verify this issue with macOS 14.4.1 Release and update your bug report with your results by logging into https://feedbackassistant.apple.com/ or by using the Feedback Assistant app.

macOS 14.4.1 Release (Build: 23E224)
https://developer.apple.com/download/
Posted Date: March 25, 2024

If resolved, you can close your feedback by choosing the Close Feedback menu item in the Actions pop-up in Feedback Assistant.

If the issue persists, please attach a new sysdiagnose captured in the latest build and attach it to the bug report. Thank you.

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https://developer.apple.com/services-account/download?path=/OS_X/OS_X_Logs/sysdiagnose_Logging_Instructions.pdf

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