We need to decide how to proceed. I don't see how we can have it both
ways -- we either allow trailing whitespace on boundary lines or we
allow one boundary string to be a leading substring of another. Which
one is more important? Requiring infinite lookahead is not acceptable in
my opinion.
The only argument I can see for allowing trailing whitespace in a boundary
is the fact that they are allowed to be defined in quotes. It doesn't make
any sense to me to require a rule which states that "boundary=" may not use
trailing white space *even if enclosed in quotes* (as was stated earlier).
Allowing free use of whitespace within a quoted field should be sacrosanct.
To counter that, I think allowing trailing whitespace makes life very
difficult for humans trying to "parse" a nontrivial MIME message. But we
can't go back now and disallow the definition of boundaries via quoted strings.
In either case, I believe we absolutely must allow a boundary string to be
a leading substring of another, otherwise any boundary generator which is
based on a characterized time stamp will break. Or to put it another way, to
specifically disallow it seems absurd!
Brent Stilley, Oklahoma State University, 113 Math Sciences, Stillwater, 74078