DISCLAIMER: This documentation is under modification.
Sendmail is a trademark of Sendmail, Inc.
[3]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.
[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.
[5]Actually, the pathname varies depending on the operating system; /etc/mail is the preferred directory. Some older systems install it in /usr/lib/, and I've also seen it in /usr/ucblib. If you want to move this file, add -D_PATH_SENDMAILCF=\e"/file/name\e" to the flags passed to the C compiler. Moving this file is not recommended: other programs and scripts know of this location.
[6]The system libraries can reference other files; in particular, system library subroutines that sendmail calls probably reference /etc/passwd and /etc/resolv.conf.
[7]Except on Ultrix, which does not support facilities in the syslog.
[8]This format may vary slightly if your vendor has changed the syntax.
[9]This is the usual value of the HostStatusDirectory option; it can, of course, go anywhere you like in your filesystem.
[10]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.
[11]Actually, any mailer that has the `A' mailer flag set will permit aliasing; this is normally limited to the local mailer.
[12]The gdbm package does not work.
[13]The AliasWait option is required in the configuration for this action to occur. This should normally be specified.
[14]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.
[15]On some systems the default is zero to turn the protocol off entirely.
[16]This verification includes looking up every address with the name server; this involves network delays, and can in some cases can be considerable.
[17]This is actually completely equivalent to $(host hostname$). In particular, a $: default can be used.
[18]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.
[19]As of version 8.6, all of these macros have reasonable defaults. Previous versions required that they be defined.
[20]For example, on some systems gethostname might return foo which would be mapped to by gethostbyname.
[21]Older versions of sendmail didn't pre-define $j at all, so up until 8.6, config files always had to define $j.
[22]The old g option has been combined into the DefaultUser option.
[23]N.B.: the noreceipts flag turns off support for RFC 1891 (Delivery Status Notification).
[24]When running as a daemon, it changes to this user after accepting a connection but before reading any SMTP commands.
[25]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.
[26]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.
[27]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.
[28]If you do, please send updates to sendmail@Sendmail.ORG.
[30]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.

[Contents] [Previous]
This document was translated by troff2html v0.21 on March 7, 2000.

Claus Aßmann Please send comments to: <ca at>