III -> V conversion

[gwyn%brl-vld at sri-unix.UUCP]

From:      Doug Gwyn (VLD/VMB) <gwyn at brl-vld>

The port from UNIX System III to UNIX System V is relatively easy.
(a) Toss ALL object and executable binaries and rebuild them from
source.
(b) STDIO buffering is different (generally better and faster) but
it is rare that an application will fail because of this change.
(c) It is always possible that the application relied on bugs that
were fixed in the later release of UNIX.
(d) Some #include files #define new symbols that have a chance of
clashing with symbols in your code.  cpp will flag these for you.