@Robert_Developer I cannot read your feedback and what's the next?

@eskimo Thanks for ur reply, and I will see what I can do.

what about float time_left = (msg-deadline * 1.f - mach_absolute_time()) / NSEC_PER_SEC; // seconds

KEXTs are deprecated and with new system extensions there is no need to cp extensions to its folder. For how to install system extensions, here we go(OSSystemExtensionRequest) - https://developer.apple.com/documentation/systemextensions/ossystemextensionrequest?language=objc And if u disabled SIP, u can install system extensions from wherever u want. On the contrary, app only in /Applications can install system extensions.