Can you link to one that has individual virtual memory processes where the memory isn't freed? It sounds like what you're talking about is just leaking memory and processes have nothing to do with it.

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reactordev 4 days ago | parent [-]

virtual memory requires pages and this sucker doesn’t have them. Only a heap that you can use with heap_x.c

Everything is manual.

I get you people are trying to be cheeky and point out all modern OS’s don’t have this problem but C runs on a crap ton of other systems. Some of these “OS” are really nothing more than a coroutine from pid 0.

I have 30 years experience in this field.

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sph 4 days ago | parent [-]

Yeah I think I get your problem. I am prototyping a message-passing actor platform running in a flat address space, and virtual memory is the only way I can do cleanup after a process ends (by keeping track of which pages were allocated to a process and freeing them when it terminates)

Without virtual memory, I would either need to force the use of a garbage collector (which is an interesting challenge in itself to design a GC for a flat address space full of stackless coroutines), or require languages with much stricter memory semantics such as Rust so I can be safe everything is released at the end (though all languages are designed for isolated virtual memory and not even Rust might help without serious re-engineering)

Do you keep notes of these types of platforms you’re working on? Sounds fun.

	▲	reactordev 4 days ago \| parent [-]
		Not anything I can share. I’m trying to modernize these systems but man oh man was the early 80s tech brutal. Rust is something we looked into heavily and are trying to champion but bureaucracy prevents us. Flight Sims have to integrate with it in order to read/write data and it’s 1000x worse than SimConnect from MSFS. The good news is that this work is dying out. There isn’t a need to modernize old war birds anymore.