Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

For variables that are only checked with defined(), don't provide
any fake value.

Use a single style for share/doc/ makefiles.

Preprocess with tbl(1).

Fixed build of recently added legacy docs.

Reviewed by: grog

Unbreak world.

Obtained from: mark
Pointy hat to: grog

Change msU macros to mU.

This is only a partial solution; the whole issue of building the
documentation needs to be revisited.

Remove original license disclaimer.
Add Caldera license.

Approved by: David Taylor <davidt@caldera.com>

Make buildable under FreeBSD. This was relatively complicated: the
original text used the msU macros, which are available in a number of
different kinds. This version uses a number of mm-like macros,
including AL and BL, which just aren't available in ms, and the msU
macros I've found (even the ones in 4.4BSD) don't have them either. I
replaced them with ms constructs, which makes it format better than
the O'Reilly document, but I wasn't able to get the table of contents
(ms doesn't have that facility).

Add a prominent comment that this is not a reference for any modern
version of C.

Initial checkin: 4.4BSD version. These files need to be updated with
current license information and adapted to the FreeBSD build
environment before they will build.

Approved by: David Taylor <davidt@caldera.com>