[TUHS] The Curious Case of "x"-suffixed Kernel Headers in 50 Changes

[segaloco via TUHS]

On Sunday, July 19th, 2026 at 03:00, Jonathan Gray via TUHS <tuhs at tuhs.org> wrote:
> 
> *x.h headers aren't in PG2 going by
> https://www.tuhs.org/Archive/Documentation/TechReports/USG_Library/1046_UNIX_Support_Classifications_for_PG_1C300_Issue_2.pdf
> 

D'oh, good catch.  I suspect that then indicates this was a very late change prior to UNIX/TS introduction and filtered out to USG and Columbus, but PWB didn't get it in time and jumped to UNIX/TS in the 2.0 days.  Too bad we can't get a file schedule of PWB 1.1 or 1.2, I wonder if either had this brief change...

Still, that makes it less likely this is some USG shenanigans and just late C-UNIX stuff prior to portability work.

- Matt G.