Physical memory access with SystemV/AT

[Charles Hedrick]

I don't understand the two messages saying they wished there were a
way to access screen memory directly.  There is, and the original
question gave it.  I even use it in my version of microemacs (the
diffs for which were posted to this group some time ago).  It uses the
shmcreate program, which can be used to create a System V shared
memory segment for a region of physical memory.  The original question
was simply whether there was a way to do this for a large segment
(other than the obvious way of using several contiguous small ones).
There is some maximum segment size documented (which I don't recall,
since my documentation is elsewhere).  It's that limitation on segment
size, not the existence of the facility, which was the subject of the
question.