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[Kurt Hackenberg]

On 12/15/18 1:01 AM, Erik Christiansen wrote:

> On 13.12.18 13:05, Kurt Hackenberg wrote:
>>
>> You may want to preserve message attributes -- things like, this message has
>> been read, this message has been replied to, this message has been flagged,
>> this message has been assigned the keyword "blorgh". Mail delivery agents,
>> including procmail, are likely to drop that information.
> 
> Hmmm ... can any of that actually be true? Let's check. Mutt makes flag
> and read status persistent through added headers such as:
> 
> Status: RO
> X-Status: F
> 
> Is it in reality even remotely "likely" that any LDA contains code to
> search out those headers and delete them in transit? (Please feel free
> to post any code snippets found.)
> 
> The assertion also seems to ignore that mutt inserts those headers
> _after_ the LDA has delivered the messages, so there is normally no
> possible opportunity for the claimed LDA header removal - is there?

That is true when the delivery agent is part of receiving a new message 
coming in from the Internet -- but that's not what I was talking about.

My message was a reply to Ian Zimmeran's suggestion to use a delivery 
agent as part of converting mail that has already been received, to a 
different storage format (converting mbox to maildir).

Ian said this:

 > For conversion, you can use formail -s together with some script that
 > will deliver to maildirs.  I can provide you with mine if you ask.
 > Also, something like
 >
 > DEFAULT=/path/to/maildir/  procmail /dev/null
 >
 > will work (but I try to avoid procmail for data-critical tasks).

See? Conversion after the fact, not original delivery.