Keith Moore wrote:
The biggest potential for unmet expectations that I see is for users of
legacy MUAs that (a) use "sendmail -t" and (b) allow message authors to
specify arbitrary headers. The potential exists for those users to
specify NoReply recipients who will not receive the message. The
document doesn't currently recommend that "sendmail" and similar
programs be upgraded to support NoReply fields, but that is probably
what should happen. Assuming that all "sendmail" and similar programs
would eventually be upgraded, this would further minimize the potential
for unmet expectations.
I feel that worries about MUAs using "sendmail -t" by existing MUAs is a
red herring.
If those MUAs were to be enhanced to support sending messages with
To/CC-No-Reply headers, they would be able to send messages to those
individuals by invoking sendmail a second time and providing those
addresses on the sendmail command line. No change to sendmail is
required -- just changes to the MUA.
Tony Hansen
tony(_at_)att(_dot_)com