Alias_sequence_* alias options
alias_sequence_suffix alias options request that a sequence number be prepended or appended to the Subject: lines of messages posted to the list. They are analogues of the legacy alias file named parameters [SEQUENCE_PREFIX] and [SEQUENCE_SUFFIX]. The
value item gives the full file path specification of a sequence number file. This file is read, incremented, and updated each time a message is posted to the list. The number read from the file is prepended, in the case of
alias_sequence_prefix, or appended, in the case of
alias_sequence_suffix, to the message's Subject: header line. This mechanism provides a way of uniquely sequencing each message posted to a list so that recipients can more easily track postings and determine whether or not they have missed any.
By default, a response to a previously posted message (with a previous sequence number) retains the previous sequence number as well as adding a new sequence number to the subject line; the build up of sequence numbers shows the entire "thread" of the message in question. However, the
alias_sequence_strip alias option (analogue of the alias file named parameter [SEQUENCE_STRIP]) can be used to request that only the highest numbered, i.e., most recent, sequence number be retained on the subject line. The
value item is currently ignored and should always be
Important note:To ensure that sequence numbers are only incremented for successful postings, an
alias_sequence_suffix alias option should always be set as the last alias option; that is, if other alias options are also being used, the
alias_sequence_* options should be set (and appear when shown) at the end of the list of alias options on an alias entry.
Sequence number files are binary files and must have the proper file attributes and access permissions in order to function correctly.