rather than the number of matching messages.
``--duplicate=N``
- Effective with ``--output=files``, output the Nth filename
- associated with each message matching the query (N is 1-based).
- If N is greater than the number of files associated with the
- message, don't print anything.
+ For ``--output=files``, output the Nth filename associated
+ with each message matching the query (N is 1-based). If N is
+ greater than the number of files associated with the message,
+ don't print anything.
+
+ For ``--output=messages``, only output message IDs of messages
+ matching the search terms that have at least N filenames
+ associated with them.
Note that this option is orthogonal with the **folder:** search
prefix. The prefix matches messages based on filenames. This