How does man know?

[Richard O'Keefe]

In article <2909 at crdgw1.crd.ge.com>, barnett at crdgw1.crd.ge.com (Bruce Barnett) writes:
> But how can I resize a window, changing the rows and columns,
> but still retain the flag that I do or do not want paging?
> Perhaps a 'stty page' is needed.
Well, you _couldn't_ change the size of the window on a terminal, so
this problem never occurred to anyone.  A separate "page" option would
appear to be the right approach.

> 	Perhaps another solution in a future version of Unix is to
> attach a process to your /dev/stdout and /dev/stdin. Something like a
> pseudo TTY in that it appears to be the stdin and stdout to all
> programs doing terminal I/O to the default device.

It has been pointed out to me that paging in SunOS is a function of
"shelltool", which works in much that fashion.  It has also been
explained to me that in the X systems I've seen (where I thought paging
was a function of "window managers") it is in fact a function of
"terminal emulators", which I believe work in much that fashion.

> I don't know if I would like it of not, but you could have your pager
> automatically pop up a new window everytime the data being displayed
> was more than a certain size.

Some Apollo commands do pop up windows; I think man(1) does this.

> What every happened to this feature? Why did it disappear from the two
> main strains?

The "E" in "EUUG V7" stands for "European".  The feature was not present
in the USA original.  Where the feature was first invented I don't know;
VM/CMS does something similar so it _must_ be an old idea.