shl and recognizing ^Z

[Tom Reingold]

Could someone describe what are shl and sxt are.  I have read about
layers but don't have a reference.  What should I read?  How do I tell
if my system has any of these?

I "grew up" on Berkeley systems, and having been moved onto System V, I
miss job control and simultaneous shells.  All this talk has me
interested, because it looks like -- with a little work -- I can get
what I want.
--
Tom Reingold
tr at samadams.princeton.edu
rutgers!princeton!samadams!tr
201-560-6082