[$] Bus1: a new Linux interprocess communication proposal

Anyone who has been paying attention to Linux kernel development inrecent years would be aware that IPC - interprocess communication - is nota solved problem. There are certainly many partial solutions, from pipesand signals, through sockets and shared memory, to more special-purposesolutions like Cross MemoryAttach and Android's binder. But it seems thereare still some use cases that aren't fully addressed by current solutions,leading to new solutions being occasionally proposed to try to meet those needs.The latest proposal is called "bus1".