[1]This is usually
/usr/sbin
on 4.4BSD and newer systems;
many systems install it in
/usr/lib.
I understand it is in /usr/ucblib
on System V Release 4.
[2]Some vendors ship them owned by bin;
this creates a security hole that is not actually related to
sendmail.
Other important directories that should have restrictive ownerships
and permissions are
/bin, /usr/bin, /etc, /usr/etc, /lib, and /usr/lib.
[3]Actually, the pathname varies depending on the operating system;
/etc is the preferred directory.
Some older systems install it in
/usr/lib/sendmail.cf,
and I've also seen it in
/usr/ucblib
and
/etc/mail.
If you want to move this file,
change
src/conf.h.
[4]The system libraries can reference other files;
in particular, system library subroutines that
sendmail
calls probably reference
/etc/passwd
and
/etc/resolv.conf.
[5]Except on Ultrix,
which does not support facilities in the syslog.
[6]This format may vary slightly if your vendor has changed
the syntax.
[7]This is the usual value of the
HostStatusDirectory
option;
it can, of course, go anywhere you like in your filesystem.
[8]Actually, any mailer that has the `A' mailer flag set
will permit aliasing;
this is normally limited to the local mailer.
[9]The
gdbm
package probably works as well.
[10]The
AliasWait
option is required in the configuration
for this action to occur.
This should normally be specified.
[11]That is, it sets its effective uid to the real uid;
thus, if you are executing as root,
as from root's crontab file or during system startup
the root permissions will still be honored.
[12]On some systems the default is zero to turn the protocol off entirely.
[13]This verification includes looking up every address
with the name server;
this involves network delays,
and can in some cases can be considerable.
[14]This is actually
completely equivalent
to $(host hostname$).
In particular, a
$:
default can be used.
[15]You may want to use it for special
``per user''
extensions.
For example, in the address
``jgm+foo@CMU.EDU'';
the
``+foo''
part is not part of the user name,
and is passed to the local mailer for local use.
[16]As of version 8.6,
all of these macros have reasonable defaults.
Previous versions required that they be defined.
[17]For example, on some systems
gethostname
might return
``foo''
which would be mapped to
``foo.bar.com''
by
gethostbyname.
[18]Older versions of sendmail didn't pre-define
$j
at all, so up until 8.6,
config files
always
had to define
$j.
[19]The old
g
option has been combined into the
DefaultUser
option.
[20]When running as a daemon,
it changes to this user after accepting a connection
but before reading any
commands.
[21]And of course, vendors are encouraged to add themselves
to the list of recognized vendors by editing the routine
setvendor
in
conf.c.
Please send e-mail to sendmail@Sendmail.ORG
to register your vendor dialect.
[22]That is, don't create new maps and then use
mv(1)
to move them into place.
Since the maps are already open
the new maps will never be seen.
[23]These instructions are known to be incomplete.
A future version of the user database is planned
including things such as finger service -- and good documentation.
[24]Actually, this is no longer true in SMTP;
this information is contained in the envelope.
The older ARPANET protocols did not completely distinguish
envelope from header.
[25]If you do, please send updates to
sendmail@Sendmail.ORG.
**Deprecated.
[26]This example is contrived and probably inaccurate for your environment.
Glance over it to get an idea;
nothing can replace looking at what your own system generates.