Message size or priority comparison rewrites

As of MS 8.0, rewrite rules can be made sensitive to the expected size and/or priority (SMTP MT-PRIORITY; see RFC 6710 (SMTP Extension for Message Transfer Priorities)) of an incoming message. Such checking is triggered by the presence of a $NcomparisonC control sequence in the template part of a rule, where N is an appropriate numeric value (which note should be in the range -9 through 9 for MT-PRIORITY checks),   is one of ,  ,  ,  ,   , or  , and where C (the characteristic code) is one of  ,  , or    (indicating message block size, message number of lines, and message priority, respectively).

So for instance the control sequences: $100&#x3c;B $2000&#x3e;=L $4=P would limit a rewrite rule to applying only when a message matched the conditions, respectively, (1) block size less than 100, (2) line size greater than or equal to 2000,  (3) MT-PRIORITY value of 4.

See also:
 * Rewrite rule template substitutions and control sequences