PTH is a very portable POSIX/ANSI-C based library for Unix platforms which
provides non-preemptive scheduling for multiple threads of execution
("multithreading") inside server applications. All threads run in the same
address space of the server application, but each thread has its own
individual program-counter, run-time stack, signal mask and errno variable.

This version makes use of the --enable-syscall-hard option that provides
replacement syscalls in libpthread. The function gives the appearance of
some preemptiveness as it provides new syscall entry points.

Homepage:
https://www.gnu.org/software/pth/pth.html
