sendmailSearch this book
Previous: 32.2 Access Class in RulesChapter 32
Class Macros
Next: 32.4 Pitfalls

32.3 Class with m4

In configuring with the m4 technique, many classes are defined for your convenience. You need to be aware of these not only to take advantage of them, but also to avoid reusing their single-character names by mistake. Table 32.1 lists all the macros that the m4 technique uses as of version 8.8.4. Most are described in other sections, but a few are described here. See Section 19.6.30, LOCAL-CONFIG for the general method used for adding members and new class names using the m4 technique.

Table 32.1: Class Macros Used with the m4 Technique
$=BSection 19.6.8, FEATURE(bestmx-is-local)Domains to lookup in bestmx in place of $=w
$=ESection 19.6.4, EXPOSED-USERList of EXPOSED USERS users
$=FU.C. Berkeley example .mc files
$=GSection 19.6.11, FEATURE(genericstable)List of other sites to look up in genericstable
$=LSection 19.6.38, LOCAL-USERList of LOCAL USER users
$=MSection 19.6.12, FEATURE(limited-masquerade)List of hosts to masquerade
$=OhereList nonusername characters
$=PhereList of pseudo domains
$=USection 19.4.6, "UUCP"Locally connected UUCP hosts
$=VSection 19.4.6Hosts connected to UUCP relay $V
$=WSection 19.4.6Hosts connected to UUCP relay $W
$=XSection 19.4.6Hosts connected to UUCP relay $X
$=YSection 19.4.6Locally connected smart UUCP hosts
$=ZSection 19.4.6Locally connected domainized UUCP hosts

The class O is used by the m4 technique to hold a list of characters that cannot be used in local usernames. This list is used to detect certain kinds of routing addresses that might otherwise be difficult to detect. This list initially contains

@ %

but may also contain a ! if UUCP support is included.

The class P holds a list of pseudo domains that will not be looked up using DNS. Unless you use a FEATURE, this class will only contain a dot. Various FEATUREs will add appropriate pseudo domains to it, such as .UUCP and .REDIRECT.

Previous: 32.2 Access Class in RulessendmailNext: 32.4 Pitfalls
32.2 Access Class in RulesBook Index32.4 Pitfalls