sendmail, 4th Edition

The Minimal mc File

Every mc file requires minimal information. Table 17-1 shows which m4 items are required and lists two that are recommended. We show them in the order that they should be declared (OSTYPE first and MAILER last), and then describe the mandatory and recommended information.

Table 17-1. Required and recommended m4 items

Item	Section		Description
OSTYPE( )	OSTYPE( ) m4 macro on page 590	Required	Support for your operating system
DOMAIN( )	DOMAIN( ) m4 macro on page 591	Recommended	Common domain-wide information
FEATURE( )	FEATURE( ) m4 macro on page 592	Recommended	Solutions to special needs
MAILER( )	MAILER( ) m4 macro on page 590	Required	Necessary delivery agents

Note that what is minimally required for a workstation differs from what is minimally required for a central mail server. We suggest that you use these recommendations as a jumping-off point and then investigate all the m4 macros and features that are available.

OSTYPE( ) m4 macro

Support for various operating systems is supplied with the OSTYPE m4 command. Every .mc file must declare the operating system with this command, and this command must be the first in your mc file.^[237] The available support is supplied by files in the _CF_DIR_/ostype directory. A listing of those files looks something like this:

a-ux.m4 bsdi2.0.m4 hpux9.m4 openbsd.m4 solaris2.ml.m4 aix3.m4 darwin.m4 irix4.m4 osf1.m4 solaris2.pre5.m4 aix4.m4 dgux.m4 irix5.m4 powerux.m4 solaris8.m4 aix5.m4 domainos.m4 irix6.m4 ptx2.m4 ...