[CentOS] Equivalent command or file

List, is there an equivalent on Linux as "watch" under FreeBSD, as well 
as the "snp" or snoop device that permits one to watch what is going on 
in another terminal?  Yes there are privacy issues here, but in a home 
system with a couple of folks logged in trying to help with compiling 
stuff, it'd be nice to see what and how they are doing it.

Thanks...

-- 
Snowman