C11 Thread support library is a portable threading C API between OSs,
similar to std::threads in the C++ world.
The library is implemented as a thin shim over POSIX interfaces.
NetBSD implements the API as a part of the POSIX threading library
(libpthread(3)).
C11 threads(3) are in the process of making them an integral part
of the POSIX standard. The interface has been implemented in major
OSs and used with stopgap libraries for older versions of them.
C11 threading library is already used (with a stopgap implementation)
in the NetBSD distribution in MESA.
Original implementation by myself from 2016.
ATF tests are new and cover almost all interfaces.
Proposed on tech-userlevel@.