mbox format?

[Stephen R. van den Berg]

The most common mailbox format (sendmail, smail or compatible environment)
is defined as follows:

Every occurrence of the following "Regular Expression" marks the beginning
of a new mail message:
\n\nFrom +[^\t\n ]+ +[^\n\t]

Any mailbox file should start with a line conforming too:
>From +[^\t\n ]+ +[^\n\t]

No, I did not find this in the manual, I just figured this out by trial
and error from the /usr/ucb/mail program included with SunOS.

Many programs erroneously allow *any* line starting with 'From ' to mark
the start of a message (not even checking if the preceding line was empty
either).
--
Sincerely,                                berg at messua.informatik.rwth-aachen.de
           Stephen R. van den Berg.       berg at physik.tu-muenchen.de

"My name is Psmith, the P is not pronounced."