David C. Brock <dbrock@computerhistory.org> wrote:
>
> I’d like to read similar discussions of the data structures for ed, em,
> ex/vi. If anyone has suggestions of references, they would be very
> welcome!

A curious one is nvi, which uses the Berkeley DB RECNO interface to access
a text file as an array of lines (RECNO = record number).

Tony.
-- 
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Sole, Lundy, Fastnet, Irish Sea, Shannon: East or northeast 4 to 6,
occasionally 7 in Lundy. Rough at first in northwest Shannon,
otherwise slight or moderate, then occasionally rough later in east
Sole. Fog patches at first in Sole. Moderate or good, occasionally
very poor at first in Sole.