Run a thread continuously without blocking main thread in swift - swift

Question

I wrote a code and I need to run it continuously. Initially I used RunLoop.current.run(). It works fine. The problem is it blocks the main thread. How can I run it in background continuously without blocking.
Basic class structure:
class Keylogger
{
func start()
{
let observer = UnsafeMutableRawPointer(Unmanaged.passUnretained(self).toOpaque())
/* Connected and Disconnected Call Backs */
IOHIDManagerRegisterDeviceMatchingCallback(manager, Handle_DeviceMatchingCallback, observer)
IOHIDManagerRegisterDeviceRemovalCallback(manager, Handle_DeviceRemovalCallback, observer)
/* Input value Call Backs */
IOHIDManagerRegisterInputValueCallback(manager, Handle_IOHIDInputValueCallback, observer);
/* schedule */
IOHIDManagerScheduleWithRunLoop(manager, CFRunLoopGetMain(), CFRunLoopMode.defaultMode.rawValue)
print("Started")
}
}
And in main.swift
var logger = Keylogger()
logger.start()
RunLoop.current.run()
// Whatever written below this will not be executed obviously
I used DispatchQueue before for background tasks( which is just a piece of code) but how to execute it continuously?
I tried this:
var d = Keylogger()
var ff = {
d.start()
}
var f = DispatchQueue(label: "Keylogger", qos: .userInteractive, attributes: .concurrent)
f.async(execute: ff)
while true
{}
But the start() of Keylogger is never executed.
I thought of creating executable and running the executable through NSTask. Other than this is there any way to do it?

Answer 1

I think you are not understanding the purpose of RunLoop.current.run().
Your code works only when your program is running. Constantly.
Your keylogger code is ran on an another thread. So, to keep that thread alive, the main thread must be active. That is the reason for RunLoop.current.run().
So, try to use callbacks(like keylogger is using) and schedule it on another thread. Or, do everything you want and place RunLoop.current.run() at the very end of your code.