Mailing List Archive: So Exim will break lines on Subject?

So I’m sending an email with a subject that looks like this

addlist Fidelity Fixed Income New Issues:intray.zalerts.fidelity.research:0

but I’m noticing that when the final text file is stored in Maildir that the subject looks like this

Subject: addlist Fidelity Fixed Income New
Issues:intray.zalerts.fidelity.research:0

ie. the newline has been added.

Is that normal behavior?

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On 2023-06-05 at 21:27:15 UTC-0400 (Mon, 5 Jun 2023 20:27:15 -0500)
Robert Nicholson via Exim-users <robert.nicholson@gmail.com>
is rumored to have said:

> So I’m sending an email with a subject that looks like this
>
> addlist Fidelity Fixed Income New
> Issues:intray.zalerts.fidelity.research:0
>
> but I’m noticing that when the final text file is stored in Maildir
> that the subject looks like this
>
> Subject: addlist Fidelity Fixed Income New
> Issues:intray.zalerts.fidelity.research:0
>
> ie. the newline has been added.
>
> Is that normal behavior?

Yes.

Mail agents may 'fold' any header at whitespace by inserting a line
break before the whitespace, optionally expanding the whitespace. See
RFC822 and its successors for all of the extremely gory details.

--
Bill Cole
bill@scconsult.com or billcole@apache.org
(AKA @grumpybozo and many *@billmail.scconsult.com addresses)
Not Currently Available For Hire

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