Callout routines

The MTA&#x27;s support for calling out to routines from mapping tables or rewrite rules is intended to allow sites to provide and use their own, site-written, routines. However, the MTA does ship with a few Oracle-provided routines as well.

See also the  routine, discussed in Spamfilter early verdicts.

See also:
 * check_memcache.so callout
 * check_metermaid callouts
 * dns_verify callouts
 * smartsend callouts
 * Spamfilter early verdicts
 * Mapping entry templates
 * Rewrite routine substitutions