[CentOS] [exim] how to check a message header for being empty

Sun Oct 5 13:50:01 UTC 2014
Always Learning <centos at u62.u22.net>

On Sun, 2014-10-05 at 12:51 +0100, Dennis Davis wrote:

> On Sat, 4 Oct 2014, lee wrote:
> 
> > Is the Subject: header required by some RFC?  If it is, I'll also
> > deny messages that don't have one.

> Not as far as I'm aware.  RFC5322, "Internet Message Format",
> contains:
> 
>    The only required header fields are the origination date field and
>    the originator address field(s).  All other header fields are
>    syntactically optional.  More information is contained in the table
>    following this definition.

There is a real difference between the lack of a Subject: header and a
present but empty Subject: header.

I reject emails with no Subject: headers but accept empty Subject:
headers because even I can occasionally forget to type-in a Subject.


-- 
Regards,

Paul.
England, EU.