This compiles, and contains exactly the same bugs as before.
The regex 'FIXME: PID/' should reveal all markers that I left behind, including:
- Incomplete conversion
- Issues or things that look fishy
- Actual bugs that will go wrong during runtime
This syscall allows a parent process to disown a child process, setting
its parent PID to 0.
Unparented processes are automatically reaped by the kernel upon exit,
and no sys$waitid() is required. This will make it much nicer to do
spawn-and-forget which is common in the GUI environment.