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Reply to "fork" is no-no but why?
No. I mean, it’ll probably work, but it’s relying on implementation details that could change. In a way it feels even safer to fork in pure Swift app's main.swift file so long as this is done as the very first thing. In C++ app globals' constructors could create threads, mutexes, call malloc and whatnot before (and during) the app hitting main(). I encourage you to run a performance test Indeed fork is not faster than posix_spawn, each took about 120 µs in a simple app. (I forked/spawned 1000 processes for accuracy).
Topic: Code Signing SubTopic: General Tags:
Mar ’24
Reply to Bluetooth: prohibiting or detecting unwanted pairing request alert on connect
It's probably related to the "Just Works" pairing method that DOESN'T happen in those cases I am seeing the alert. Got some heavy-wight workaround idea sketch: split the app into two with the second one being background only process. Specify CBConnectPeripheralOptionNotifyOnConnectionKey / CBConnectPeripheralOptionNotifyOnDisconnectionKey, CBConnectPeripheralOptionNotifyOnNotificationKey keys being false and make the "connect" call from there. Then somehow (XPC?) communicate data back to the main app. There must be an easier way!
Mar ’24
Reply to pthread -> NSThread
I was thinking of setting up a signal handler that does Thread.current and assigns the result somewhere (e.g. to a global variable). And then pthread_kill(...) to invoke that signal handler on the thread in question. Do you think this won't work? All the mentioned API's included signal and pthread_kill seem to be supported.
Topic: App & System Services SubTopic: General Tags:
Mar ’24
Reply to Right way to call `host_processors`
I see. Is there a path that doesn't involve privilege escalation? I am thinking of using task_threads + thread_info (with THREAD_BASIC_INFO to get cpu_usage) and somehow determine which processor/core the thread is currently assigned to (†) and then accumulate cpu usages per processor/core. This will only account for threads in the current app but for my purposes this would be enough. (†) - pthread_cpu_number_np doesn't return sensible results for me.
Topic: App & System Services SubTopic: Core OS Tags:
Mar ’24
Reply to DispatchQueue.count > thread.count case
Let me try: let queues = (0 ..< 200).map { i in DispatchQueue(label: "queue-\(i)", serial or concurrent) } queues.forEach { queue in queue.async { while true { // doing something lengthy here is Thread.current unique? In other words was a dedicated thread allocated for this queue? or could a single thread serve several queues? } } } In my tests so far a unique thread is allocated per queue.
Apr ’24
Reply to `getifaddrs` "struct ifa_data"
Right... I'm still curious though how to properly read this specific part of the documentation: For all other address families, it contains a pointer to the struct ifa_data (as defined in include file <net/if.h>) which contains per-address interface statistics. as I do not see "struct ifa_data" anywhere...
Apr ’24