Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

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

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Flush the scriptfile whenever we see a non-graphical character to get
more real-time logging, without forcing a write(2) on every single
character.

Fix compilation warnings (up to level 3).

Resolve merge conflicts.

Fix merge conflicts, and because this still has a zillion warnings,
protect the build with a WARNS=2.

Fix the build.

Use STD{ERR,IN,OUT}_FILENO instead of their numeric values. The
definitions are more readable, and it's possible that they're
more portable to pathalogical platforms.

Submitted by: David Hill <david@phobia.ms>

If the user exists abruptly, tip's "tipout" child can hang around
forever. Since the lock file doesn't get cleaned up, this prevents
other users from accessing the target device.

(phk adds: Man, this has been bugging me for YEARS!)

PR: 12528
Submitted by: Craig Leres leres@ee.lbl.gov
MFC after: 1 week

#include <errno.h> where needed. Kill extern int errno;.

Minor warnings in tip corrected.

$Id$ -> $FreeBSD$

Change from using sys/param.h and MAXPATHLEN to using limits.h and PATH_MAX
to avoid the NOFILE problem. Back out NOFILE kludge. Fix unexploitable
buffer overflow in tipout.c.
Reviewed by: millert@openbsd.org (tipout.c)
Submitted by: millert@openbsd.org (rest of idea)

Add prototypes, usage(). Use err(3).

We wouldn't want to kill init if our parent died...

Spotted by: davidg

Die if we get errors from the tty.

Tom Gray's new tip changes to support a modem capabilities database and
fixes to many assorted bugs and misfeatures.
Submitted by: Tom Gray - DCA <dcasba@rain.org>