SpecOS

A multi-threaded-style OS for the Spectrum +3.

Based on a kernel/userland model, it decouples the kernel implementation from the run-time system call mechanism, and provides for some POSIX-style functions. A file descriptors layer provides abstraction for easy file redirection.

Userland processes are relocatable, and have no knowledge of the kernel or memory layout, leaving the flexibility to change the memory paging model without requiring a recompile of all userland programs.