how do I tell the size of a pseudoterm window?

[Guy Harris]

>There is an equivalent but different pair of ioctls on older SunOS's.

Actually, TIOCGWINSZ/TIOCSWINSZ have been in SunOS since 3.2, although
they weren't documented until 4.0.  The pre-4.0 version didn't store the
"pixel" sizes, but just returned them as zero.

>There doesn't appear to be such functionality in SystemV (they have
>a different philosophy about what a window is, I think).

No, it's just that they don't have pseudo-ttys; pseudo-ttys are actually
a general mechanism; many window systems use them to provide "terminal
emulator" windows. 

S5 doesn't come standard with a window system (unless S5R3.2 comes
standard with X11), so it really doesn't have a philosophy about what a
window is.  You can get support for the various AT&T bit-mapped
terminals as an add-on package for S5; those do handle terminals with a
mechanism other than pseudo-terminals (the "terminal emulator" window
code runs in the terminal itself, so each such window sort of uses a
channel provided over a serial link), but I think it has an "ioctl"
that's similar to TIOCGWINSZ, named JWINSIZE.  ("J" stands for "Jerq",
which, as I understand it, was the original name of the BTL Research
bit-mapped terminal, before it was named the Blit.)

Then again, 4.xBSD doesn't come standard with a window system, either
(unless 4.3-tahoe comes standard with X11), so it doesn't really have a
philosophy about what a window is, either. 

If S5R3.2 comes with X11, I suspect it also provides pseudo-ttys and
TIOCGWINSZ/TIOCSWINSZ.