Avoiding expansion of mail's metacharacters

Larry Campbell campbell at maynard.UUCP
Tue Aug 20 11:13:55 AEST 1985


> > There's an obvious and easy way to fix this problem.
> > 
> > Put ALL the information in the input file!
> > 
> > The only information that needs to go over the uucp link is "run this
> > program on this input file".  No argv.  The shell is happy to
> > deal with that, and the program is free to place any interpretation 
> > on the input file.
> 
> This won't always work.  Suppose you've got a message
> 	To: ihnp4!cbosgd!bill, decvax!decwrl!june, sdcsvax!sdcc3!george,
> 	    ucbvax!ucbfunky!ellen
> 
> When ihnp4 gets this message, what should it conclude?  That it should
> only try to deliver the copy to "ihnp4..."?  Even if it has
> direct paths to sdcsvax and ucbvax?  Or should it just try to deliver
> to everyone?...
> 
> 	Joel West	CACI, Inc. - Federal (c/o UC San Diego)
> 	{ucbvax,decvax,ihnp4}!sdcsvax!jww
> 	jww at SDCSVAX.ARPA

You're confusing the envelope with the message.  Conceptually, the mail
command line is the "envelope", containing delivery instructions.  The
message header lines are part of the message, ignored by intermediate
delivery agents, and used only by the final recipient.  (I'm speaking
simplistically and ideally here...)

To avoid shell metacharacter expansion, we just need to add an "envelope"
portion of the message that contains delivery instructions.  The "To:"
field in the message is for the recipient's benefit only;  the envelope
portion would control delivery actions.

Unfortunately, in today's far from perfect world, it often becomse
necessary for some intermediate delivery agent to edit the message header
as well, or else replies won't work.  We should regard this as a temporary
aberration, which can be dispensed with when a universal mail addressing
scheme has been adopted.  This might even happen within our lifetimes!

Larry Campbell                     decvax!genrad
The Boston Software Works, Inc.                 \
120 Fulton St.                 seismo!harvard!wjh12!maynard!campbell
Boston MA 02109                         /       /
                                   ihnp4  cbosgd

ARPA: campbell%maynard.uucp at harvard.arpa



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