Are there still any V6 C compilers?

[utzoo!duke!decvax!ucbvax!KLH at SRI-KL]

From: KLH at SRI-KL
Frequently when writing code that may be useful to other
sites, I wonder to what extent I should use the V7 C features
such as long integers.  At the January '81 Usenix, the Western
Electric toady mumbled something about being able to get any
C compiler you wanted, as long as you were licensed for some
flavor of Unix.  Given that this is true, are there any good
reasons NOT to write all new subroutines, programs, etc for
the V7 C compiler?  Are there any sites still stuck with V6 C?
   The picture is a little confused because there are some
aspects of V7 code that depend on the V7 kernel or the V7
include files; not necessarily the V7 version of C.  My own
site doesn't help clear this up either since I am running the
so-called phototypesetter C, which is apparently almost but
not quite identical to the official V7 C.  (My system is V6, but
I have all the V7 include files and try to run converted V7
utilities whenever reasonable).
   This is a reasonably serious problem.  If I were to re-structure
my NCP code to handle 96-bit leaders properly (i.e. flush the
mapping/stretching patch), is there any problem with doing it
all in V7 syntax?  Would anyone be unable to use the new stuff
even if they wanted to?
--Ken
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