Subject: Re: bin/3286: sendmail doesn't escape 'From'
To: None <mouse@Rodents.Montreal.QC.CA>
From: Mike Long <>
List: netbsd-bugs
Date: 03/04/1997 13:53:05
>Date: Tue, 4 Mar 1997 12:32:47 -0500 (EST)
>From: der Mouse  <mouse@Rodents.Montreal.QC.CA>
>>> The rule that mail.local uses is that if the line starts with
>>> "From " *and* the previous line was blank, it sticks a ">" in front;
>>> otherwise it leaves it unchanged.  This gets along well with
>>> Berkeley Mail, which requires the blank line to recognize a new
>>> message, but not so well with other mailers.
>Then, I believe, the "other mailers" are broken; a message boundary in
>the mbox file format is defined to be "From " immediately following two
>consecutive newlines (with an implicit message begin at the beginning
>of the file).  Always has been.  If some UAs mistake "From " after one
>(but not two) newlines for a message boundary, then their mbox parsing
>code is simply broken, as much so as if it mistook any other string for
>a message boundary.

Regardless of whether the third-party mailers are broken, we should
change mail.local to accomodate them.  Even if all of the broken MUAs
were fixed today, it would take *years* for those fixes to propagate
to the installed base.  The fact that a few more instances of "^From "
get turned into ">From " is a small price to pay, IMHO.  It's not like
it would be the first time BSD code was changed to accomodate a large
buggy installed base (TCP_COMPAT_42 anyone?).
Mike Long <>     <URL:>
VLSI Design Engineer         finger for PGP public key
Analog Devices, CPD Division          CCBF225E7D3F7ECB2C8F7ABB15D9BE7B
Norwood, MA 02062 USA       (eq (opinion 'ADI) (opinion 'mike)) -> nil