disallowing subshell in More

[Guy Harris]

> I thought I'd throw in my 10 cents worth :
> Setting $SHELL is *NOT* going to work.
> 
> I remember using a games account, with SHELL set to something
> funny. The way to get a shell was the following :
> - Run a game that gave help.
> - Ask for the helpfile (which was, of course, given to more)
> - Startup 'vi' with the v command.
> - do a ':set shell=/bin/sh'
> - Type ':sh'
> Et voila........

It's beginning to look like the law of diminishing returns is taking
effect - you might want to write a simple pager that doesn't do anything
other than page files.  (I didn't even think about "more"s escape to "vi",
because I never use it - that's one problem with big programs with a large
set of features that few people are 100% familiar with.)  Try "p", shown
in Kernighan and Pike starting on p. 180.

	Guy Harris
	{seismo,ihnp4,allegra}!rlgvax!guy