PMDF System Manager's Guide

Messages sent via a SET FORWARD to PMDF are for the most part handled in the same way as messages sent to PMDF directly. An exceptional case arises, however, when PMDF delivers a message to a local VMS MAIL address that is in turn forwarded back to PMDF via a SET FORWARD directive. PMDF detects this case and handles it as a special type of forwarding. In particular:

1. The message RFC 822 header already attached to the message is kept as message header and modified. In contrast, manually forwarded messages receive two headers --- the original header, which becomes part of the body of the message, and a new header which is added as the message is forwarded. This handling applies regardless of how PMDF has been configured to handle message headers during local delivery (that is, the headerbottom and headeromit channel keywords have no effect on forwarding).
2. Since such messages always have a Date: header already attached, a Resent-Date: header is added instead of a Date: header. No time stamp header is added if the message had both a Date: and a Resent-Date: header already. (Note that a Received: header is always added and this header does provide some time stamp information.)
3. A From: header is only attached if the message does not have one already. Resent-from: headers are never added.
4. A Resent-To: is added if a To: header is already present; a To: header is added if no To: header is present in the original message.
5. Although the code to add user-specified headers is executed, it has no effect since this type of forwarding is handled at a system level; it is not handled under the control of the user's account. System-wide settings of user-specified headers will be applied, however.