RFC 1893 (rfc1893) - Page 2 of 15
Enhanced Mail System Status Codes
Alternative Format: Original Text Document
RFC 1893 Mail System Status Codes January 1996 space for delivery notification reporting will reduce the available codes for new ESMTP extensions. The following proposal is based on the SMTP theory of reply codes. It adopts the success, permanent error, and transient error semantics of the first value, with a further description and classification in the second. This proposal re-distributes the classifications to better distribute the error conditions, such as separating mailbox from host errors. 2. Status Codes This document defines a new set of status codes to report mail system conditions. These status codes are intended to be used for media and language independent status reporting. They are not intended for system specific diagnostics. The syntax of the new status codes is defined as: status-code = class "." subject "." detail class = "2"/"4"/"5" subject = 1*3digit detail = 1*3digit White-space characters and comments are NOT allowed within a status- code. Each numeric sub-code within the status-code MUST be expressed without leading zero digits. Status codes consist of three numerical fields separated by ".". The first sub-code indicates whether the delivery attempt was successful. The second sub-code indicates the probable source of any delivery anomalies, and the third sub-code indicates a precise error condition. The codes space defined is intended to be extensible only by standards track documents. Mail system specific status codes should be mapped as close as possible to the standard status codes. Servers should send only defined, registered status codes. System specific errors and diagnostics should be carried by means other than status codes. New subject and detail codes will be added over time. Because the number space is large, it is not intended that published status codes will ever be redefined or eliminated. Clients should preserve the extensibility of the code space by reporting the general error described in the subject sub-code when the specific detail is unrecognized. Vaudreuil Standards Track



