EvenBetterAuthorizationSample states that it is not currently posible for a XPC-based launchd daemon to safely adopt launchd transactions or take advantage of XPC transactions, but [the launchd docs] seem to indicate that the ReadMe might now be a bit out of date.
Is it recommended to use those keys?
In general we recommend that you support pressure exit because it give good performance by default and good memory behaviour on memory-constrained systems.
Will a XPC transaction be "held" until the the reply block is called for any exported NSXPCConnection interface method that requires a reply?
Yes. For standard request/reply IPCs, NSXPCConnection takes care of the transaction support for you much like the C API.
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Apple Developer Relations, Developer Technical Support, Core OS/Hardware
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