message: Responses

 
 5.1 Responses
 =============
 
 To determine where a message is to go, the following algorithm is used
 by default.
 
 “reply”
      A “reply” is when you want to respond _just_ to the person who sent
      the message via mail.  There will only be one recipient.  To
      determine who the recipient will be, the following headers are
      consulted, in turn:
 
      ‘Reply-To’
 
      ‘From’
 
 “wide reply”
      A “wide reply” is a mail response that includes _all_ entities
      mentioned in the message you are responding to.  All mailboxes from
      the following headers will be concatenated to form the outgoing
      ‘To’/‘Cc’ headers:
 
      ‘From’
           (unless there’s a ‘Reply-To’, in which case that is used
           instead).
 
      ‘Cc’
 
      ‘To’
 
      If a ‘Mail-Copies-To’ header is present, it will also be included
      in the list of mailboxes.  If this header is ‘never’, that means
      that the ‘From’ (or ‘Reply-To’) mailbox will be suppressed.
 
 “followup”
      A “followup” is a response sent via news.  The following headers
      (listed in order of precedence) determine where the response is to
      be sent:
 
      ‘Followup-To’
 
      ‘Newsgroups’
 
      If a ‘Mail-Copies-To’ header is present, it will be used as the
      basis of the new ‘Cc’ header, except if this header is ‘never’.