[AndyKelley]

Here's another implementation that works on Windows too: https://github.com/andrewrk/libsoundio/blob/master/src/ring_...

[csl]

This seems to use modulus. The whole point of the mmap trick is to get the kernel/MMU to do the work for you, IIRC.

EDIT: Oops, I see they use mirrored memory here as well.