bf_copy question

[R Kimber]

This may seem a naive question, but what exactly does bf_copy do?

the syntax is bf_copy <path>/A <path>/B and the manpage says that it copies
a bogofilter working directory to another directory.  But does this mean
that it only copies the contents of A to the pre-existing directory B, or
does assume B does not exist and tries to create B first? If the latter,
what error code does it produce if B already exists?

The reason why I ask is that I use it in a backup script and at the point
where bf_copy is running I get a message via cron saying
   mkdir: cannot create directory ‘<path>/.bogofilter’: File exists
the script does not use mkdir, so I'm assuming the error comes from bf_copy.

- Richard
-- 
Richard Kimber