It’s not a “Linux signal handler”. “POSIX” or “Unix” might be a better description, though they are also defined in the C spec. The first thing I’d do is look at the generated assembler. Does it optimise-away the 5/0 ?

Your question seems related to a consumer feature No it isn’t, it’s just spam.

I'm not in the US, I'm in HK. But the app still asks for US documents. That surprises me. Are you sure that there wasn't some earlier step where you should have changed a setting to indicate HK? Or maybe it is trying to guess where you are from your device localisation or some attribute of your Apple ID. Does the App Store know you are in HK? Is your payment card HK-issued? (This is just a guess. I have no particular insight into what is going wrong.)

I think the answer is basically "no", but you do have the option of discouraging new users by increasing the price to something no-one sane would pay.

iOS apps can only do BT LE, not classic BT.

if a customer provides this to you, you can verify if that Apple ID has a purchase for your app. Did you mean to write "Order ID" there? If you do mean "Apple ID", please explain.

But the app requires US driver’s license or state identification card to verify. I'm not a US citizen It does, generally, work for those of us outside the US. I forget exactly what documents I had to provide but it can’t have been difficult. Are you, perhaps, living in the US but not a citizen? What country are you in? Forum posts do suggest that the app is more reliable than the website so I suggest that you persevere with that. Good luck.

Can I ask apple to refund specific order from website or help center? No.

If they send you an “order ID”, which they can find in their App Store purchase history, you can look that up using the App Store Server API and get the status of their transactions. The usefulness of this is limited though. For example, these are not linked to email addresses so you can’t be sure that the Order ID is actually for this user. And it only works for in-app purchases, not for the initial app purchase. In most cases it is better to direct users to contact Apple if they have e.g. payment problems.

https://www.apple.com/uk/newsroom/2023/05/app-store-stopped-more-than-2-billion-in-fraudulent-transactions-in-2022/ Apple refused 105,000 developer account applications in 2022. Their algorithm has said no, and I suspect there is nothing you can do about it. I find this constantly terrifying.

Interesting. Presumably append is calling the getter and setter. Presumably the getter is not copying the entire array. But the Swift Array is a value-type (i.e. a struct), not an objC-compatible class, right? So I think this relies on some new Swift copy-on-write magic, not objC-style ARC, right? It would be interesting to see the implementation of append.

I tried everything Really? Every combination of… d m y, m d y, y m d -, / leading 0 or not 2 or 4 digit year I got this date from the tax form. I hope you’re using your actual datr of birth, right? Suggestion: use your web browser’s developer features to inspect the javascript and see what is is checking for. There may be a regular expression or similar in there.

Well it clearly is invalid - there are only 12 months in the year! I would like to think that tapping the ‘?’ button would give you a hint about the acceptable format. It might also expect you to use / as the separator rather than -.

How can I ensure that the new app will be recognized as an update rather than a new app? Use the same bundle ID.