[nmh-workers] inc only incorporates one email from spool

[scrumpyjack]

hi all

I'm on mac osx, downloading IMAP email using fetchmail + procmail.
Procmail is writing to a spool file like so:

:0
${HOME}/mail/spool

When I incorporate mail with
inc +inbox -file ~/mail/spool

I only get the oldest (first at the top of the spool file) email 
incorporated into my inbox.
If I add -truncate, inc incorporates the oldest top email only, 
truncates it, then exits.

Is this normal? It doesn't seem to behave like that on linux, it 
incorporates all the emails in the spool file.

nmh-1.7 built 2017-11-23 15:58:34 +0000 on Sierra
Mac OSX Darwin Kernel Version 16.7.0

--

Not sent from a tablet or smartphone.