Alphabetized sendmail Macros

The sendmail program reserves all lowercase letters, punctuation characters, and digits for its own use. For multicharacter names, it reserves all those that begin with an underscore or a lowercase letter. Table 21-7 lists all the macro names that have special internal meaning to sendmail. Included in this list are macros that are used by the mc configuration technique.[312]

Table 21-7. Reserved macros





$_ on page 801

RFC1413-validation and IP source route


$a on page 802

The origin date in RFC822 format


${addr_type} on page 803

Is address recipient/sender header/envelope


${alg_bits} on page 804

The number of bits in the TLS cipher


${auth_authen} on page 804

RFC2554 AUTH credentials


${auth_author} on page 805

RFC2554 AUTH= parameter


${auth_ssf} on page 806

AUTH encryption key length


${auth_type} on page 806

Authentication mechanism used


$b on page 807

The current date in RFC2822 format


${bodytype} on page 808

The ESMTP (Extended SMTP) BODY parameter


$B on page 808

The BITNET relay (mc configuration, deprecated)


$c on page 808

The hop count


${cert_issuer} on page 809

Distinguished name of certificate signer


${cert_md5} on page 809

MD5 of cert certificate


${cert_subject} on page 809

The cert subject


${cipher} on page 809

Cipher suite ...

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