Function init_sv 

pub unsafe fn init_sv() -> Result<(), SvInitError>

Initialises the supervisor process. If this function errors, then the supervisor process could not be created successfully; else, the caller is now the child process and can communicate via do_ffi, receiving back events at the end.

Safety

The invariants for fork() must be upheld by the caller, namely either:

• Other threads do not exist, or;
• If they do exist, either those threads or the resulting child process only ever act in async-signal-safe ways.