The NetBSD Project has announced the release of version 7 of the operating system, which is known for its portability.
Acceleration, with a direct rendering manager (DRM) and kernel mode-setting (KMS), is now available on recent Intel and Radeon graphics chips.
The new version ships with a daemon, blacklistd, which can block unwanted network connections.
The installer now supports GPT-partitioned disks.
ARM multiprocessing is now possible, and several ARM-based single board computers are now supported.
NetBSD now has an experimental port to certain Psion PDAs.
(Score: 3, Informative) by coolgopher on Monday October 12 2015, @01:17AM
Ignoring the extraneous "a", I'd assume the answer is that it's one or more regular unix domain socket (AF_UNIX). See unix(7).