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Okay, so there are no kernel pthreads. But could other pthread resources be usable in the kernel. The short answer is no. Consider mutexes, for example. By definition, a mutex can only be used within threads of the current process (or task groups as they are often called in NuttX). They have no meaning outside of the task group. Since the kernel thread "task group" can have no pthreads, how could these mutexes be used under the proper standard definition of what a mutex must be?

This is true of all pthread interfaces:  None of the pthread interfaces were intended from inter-process communications.

Roadmap

As alluded to before about the appropriateness of pthread in the OS. There is a roadmap for these kinds of features. That roadmap is to continue to conform strictly to the standard OS definitions of Opengroup.org and to continue to evolve as a fully compliant, very standard, tiny Unix-like operating system.

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