In message <20011218182437.C15801@moghedien.mukappabeta.net>, Matthias Buelow w
rites:
>Michael Kukat writes:
>
>>This is a bit strange, as i used the echo of the IRIX ksh, and this is the
>>same effect of all the other commercial OSes ksh versions, which i just think
>
>All commercial systems which come with ksh normally use System V
>semantics...
>
>>I never saw the case of a shell using the external things first, ignoring the
>>builtins. If you want to use the external program, you just give the path
>>with it, what should you do to explicitly use the builtin version? All the
>>shells i know first use the builtins before using external stuff with the sam
>e
>>names...
>
>Yes, the shell configures itself at compile time so that the behaviour
>of the builtin matches that of the system's external command (it's
>basically a decision if you're running in a SV or BSD environment.)
>

Dave Korn's office is just down the hall from me -- if you want, I can 
get an authoritative answer...  (For the record, even very early 
versions ran on both 4.1bsd and System III, and perhaps even earlier 
systems than those.)

		--Steve Bellovin, http://www.research.att.com/~smb
		Full text of "Firewalls" book now at http://www.wilyhacker.com