portability changes

finish uid_t/gid_t conversion; allow locally customized message for
prepending to all error returns

fix bogus envelope problem in clock-driven queue runs; misc. fixes

fix confusion regarding quoting with fuzzy local name matching resulting
from 8-bit clean conversion

fix small bug in buildfname

miscellaneous changes to improve logging and messages

reduce number of instances of CurEnv by passing it as a parameter

change setproctitle so it will print sendmail: in 4.4bsd

child pid not getting changed; \quoted names were still forwarded

make eight-bit clean; backslashes are carried through as-is

many fixes to controlling user code; fix Neil Rickert's hack using
CNAME for someone else's host

open connection caching

make GECOS matching configurable, and look at aliases after a match

ignore setuid bits on files if address was passed through a .forward
or :include: file -- this avoids a security problem that comes up
with System V Release 4, reported by Dave Borman

add generalized database mapping (using the K config line and
$( ... $) syntaxes); $[ ... $] is now a special case

make C option safe; output values of $r and $s macros to qf; allow
long messages in queue files

properly set up envelope when returning email; try to eliminate
some of the CurEnv globals

reject connections more quickly if load average goes up;
try to time out on opens of .forward files on hung filesystems

allow on-line comments; don't double-parse RCPT To: addresses;
warn on truncated lines; do some sanity checks on .cf file descriptor

add new 'V' config line to control configuration syntax version

from Bryan Costales: several smallish changes, mostly to clean
up debugging output. The major change is that test mode (-bt)
doesn't automatically run through ruleset three any more.

clean up #ifdef configuration to more cleanly match the modern age

allow limited 8-bit support; allow [TCP] as an alias for [IPC], even
though it's wrong; restore t option for System V support; add L=_N_
mailer option for line lengths; implement R mailer flag to get

allow limited 8-bit support; allow [TCP] as an alias for [IPC], even
though it's wrong; restore t option for System V support; add L=_N_
mailer option for line lengths; implement R mailer flag to get
restricted port; misc cleanup

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include defaults for SendMode and ErrorMode; never ignore single dot
termination when collecting message in SMTP mode.

mark tempfail during initial usersmtp open to avoid extra connections
in the future