$=R

Hosts for whom to relay V8.9 and later

The class $=R holds as its list of values the host and domain names that sendmail should allow mail to be relayed to. This $=R class should not be used directly because it could change without notice in future versions of sendmail. See RELAY_DOMAIN (The RELAY_DOMAIN mc macro on page 269) and RELAY_DOMAIN_FILE (The RELAY_DOMAIN_FILE mc macro on page 269).

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