Lines Beginning with "From" Dash-Escaped?

[Florian Weimer]

Nick Andriash <andriash@home.com> writes:

> The dash/space is only applied if "From" starts a sentence, and the word
> must be capitalised. "From" by itself is not affected.

Only lines are escaped which start with the string "From ".

> Although I've heard of some MUA's that use "From" as a delimiter,
> I've never seen it used.

The "From " delimiter is used by the UNIX mailbox format.

> Can anyone expand on the reasons why PGP and GPG use the dash-escape in
> this manner, aside from what is written in the RFC?

It's required for interoperability with mail delivery agents in the
UNIX world.

BTW, I think GnuPG doesn't escape this lines unless you've enabled
this feature using the "escape-from-lines" option in the configuration
file.