The kernel provides a number of ways for processes to communicate with each
other, but they never quite seem to fit the bill for many users. There are
currently a few proposals for interprocess communication (IPC) enhancements
circulating on the mailing lists. The most straightforward one adds a new
system call for POSIX message queues that enables the addition of new
features. For those wanting an entirely new way to do interprocess
communication, there is a proposal to add a new subsystem for that purpose
to io_uring. Finally, the bus1 proposal has made a return after ten years.