- DISCLAIMER: This documentation is under modification.
- Sendmail is a trademark of Sendmail, Inc.
- This is usually
on 4.4BSD and newer systems;
many systems install it in
I understand it is in /usr/ucblib
on System V Release 4.
- 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, /etc/mail, /usr/etc, /lib, and /usr/lib.
- Actually, the pathname varies depending on the operating system;
/etc/mail is the preferred directory.
Some older systems install it in
/usr/lib/sendmail.cf, and I've also seen it in
/usr/ucblib. If you want to move this file,
to the flags passed to the C compiler.
Moving this file is not recommended:
other programs and scripts know of this location.
- The system libraries can reference other files;
in particular, system library subroutines that
sendmail calls probably reference
- Except on Ultrix,
which does not support facilities in the syslog.
- This format may vary slightly if your vendor has changed
- This is the usual value of the
it can, of course, go anywhere you like in your filesystem.
- HP-UX 10 has service switch support,
but since the APIs are apparently not available in the libraries
sendmail does not use the native service switch in this release.
- Actually, any mailer that has the `A' mailer flag set
will permit aliasing;
this is normally limited to the local mailer.
gdbm package does not work.
AliasWait option is required in the configuration
for this action to occur.
This should normally be specified.
- 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.
- On some systems the default is zero to turn the protocol off entirely.
- This verification includes looking up every address
with the name server;
this involves network delays,
and can in some cases can be considerable.
- This is actually
to $(host hostname$).
In particular, a
$: default can be used.
- You may want to use it for special
per user extensions.
For example, in the address
+foo part is not part of the user name,
and is passed to the local mailer for local use.
- As of version 8.6,
all of these macros have reasonable defaults.
Previous versions required that they be defined.
- For example, on some systems
gethostname might return
foo which would be mapped to
- Older versions of sendmail didn't pre-define
$j at all, so up until 8.6,
always had to define
- The old
g option has been combined into the
noreceipts flag turns off support for RFC 1891
(Delivery Status Notification).
- When running as a daemon,
it changes to this user after accepting a connection
but before reading any
- And of course, vendors are encouraged to add themselves
to the list of recognized vendors by editing the routine
conf.c. Please send e-mail to sendmail@Sendmail.ORG
to register your vendor dialect.
- These instructions are known to be incomplete.
Other features are available which provide similar functionality,
e.g., virtual hosting and mapping local addresses into a
generic form as explained in cf/README.
- 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.
- If you do, please send updates to
- 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.
This document was translated by troff2html v0.21 on March 7, 2000.
Please send comments to:
<ca at sendmail.org>