Add disabled support for saving and restoring the symbol table.

Use C89 function definitions

branches: 1.11.6;
resolve conflicts.

Completely rework how tools/compat is done. Purge all uses/references to
_NETBSD_SOURCE as this makes cross building from older/newer versions of
NetBSD harder, not easier (and also makes the resulting tools 'different')

Wrap all required code with the inclusion of nbtool_config.h, attempt to
only use POSIX code in all places (or when reasonable test w. configure and
provide definitions: ala u_int, etc).

Reviewed by lukem. Tested on FreeBSD 4.9, Redhat Linux ES3, NetBSD 1.6.2 x86
NetBSD current (x86 and amd64) and Solaris 9.

Fixes PR's: PR#17762 PR#25944

branches: 1.9.2;
Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22365, verified by myself.

Protect __RCSID and __COPYRIGHT from being invoked if not defined.

Pull in various changes from OpenBSD, most from Marc Espie, including:
* Provide some GNUisms as extensions.
* Provide dynamically growable string space.
* Make define(defn(foo)) work correctly for builtins.
(The current version is supposed to be capable of satisfying autoconf.)

All still relevant NetBSD changes have been preserved in this version, and
formatting and style fixes have been applied in various places.

Thanks to Masao Uebayashi <uebayasi@soum.co.jp> for pointing this out.

WARNSify, fix .Nm usage, getopt returns -1 not EOF, deprecate register

upgrade to 4.4-lite m4. no local changes of note

latest m4 from ozan. now does the right thing w/respect to sendmail

Add RCS identifiers, remove some completely useless RCS logs and patchkit
headers, and a few other insignificant changes.

baseline of new version of m4 supplied by Ozan Yigit, original author
of the broken m4 we had. This is his stuff virgin + our Makefile.

branches: 1.1.1;
Initial revision