> You know, I was as positive as you are until I read what RFC 2821 (4.5.4.1 > Sending Strategies) has to say: > "In a typical system, the program that composes a message has some > method for requesting immediate attention for a new piece of outgoing > mail, while mail that cannot be transmitted immediately MUST be queued and > periodically retried by the sender."
Contextually, section 4.5.4.2 is a description of common configurations for *normal* mail delivery, not the special case we've been discussing. "The common structure of a host SMTP implementation includes user mailboxes, one or more areas for queuing messages in transit, and one or more daemon processes for sending and receiving mail. The exact structure will vary depending on the needs of the users on the host. We describe several optimizations that have proved helpful, particularly for mailers supporting high traffic levels." The applicable paragraph is in section 3.7: Many mail-sending clients exist, especially in conjunction with facilities that receive mail via POP3 or IMAP, that have limited capability to support some of the requirements of this specification, such as the ability to queue messages for subsequent delivery attempts. For these clients, it is common practice to make private arrangements to send all messages to a single server for processing and subsequent distribution. SMTP, as specified here, is not ideally suited for this role, and work is underway on standardized mail submission protocols that might eventually supercede the current practices. In any event, because these arrangements are private and fall outside the scope of this specification, they are not described here. So, I'd argue that 4.5.4.2 doesn't apply to the situation we're discussing. > A pox upon the authors. It confusingly uses the word "typical" and "MUST" > in the same sentence. I fear the "typical" part applies only to the > attention-getting device, allowing for > I'll-scan-the-input-queue-occassionally implementations (ok for batch). It > is hard to justify an accidental use of MUST. Your lawyers can call my > lawyers and do lunch. :-) Well, it's correct for the scenario it describes. Poorly worded, though, I'd agree. -- db ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390
