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Hi, so I have this case where I would like the user to pick a folder where they want to create a file/folder using UIDocumentPicker/Browser and I make the file using open() in cpp and use its fd to read/write to the file. Now, the first thing is I have to call startAccessingSecurityScopedResource() on the directory url, then I make the file, get its fd(file descriptor) and I leave this makefile() function. Every startAccessingSecurityScopedResource() needs to be matched with a stopstartAccessingSecurityScopedResource(). So my question is do I 'have' to call stopAccessingSecurityScopedResource() 'just before' calling close() on the fd. Or is it fine to call it after I have made the fd i.e., at the end of the makefile() function? In the tests I did it seems that once the fd is opened, even if stopAccessingSecurityScopedResource() is called on it(the directory), I can continue to read/write from the fd until I close() the fd?

So, I'm looking into startaccessingsecurityscopedresource() function and from my current understanding this is to get temporary access to files/folders you don't implicitly have access to i.e., that don't belong to your sandbox. I can understand what it means wrt macOS, iOS, iPadOS, but what does it mean in watchOS and tvOS where there isn't any file sharing between different apps? And what is it's relevance wrt using iCloud (if there is any?)