Those are all RPC mechanisms, not an ABI. They exist at a much higher level. You could have an RPC protocol be your only interface to the OS, and that would be a valid design, but would have a performance cost (see the classic Tanenbaum–Torvalds debate)
Those are all RPC mechanisms, not an ABI. They exist at a much higher level. You could have an RPC protocol be your only interface to the OS, and that would be a valid design, but would have a performance cost (see the classic Tanenbaum–Torvalds debate)