Q: How can I view the recipients of LISTSERV super-lists?

Answer by Liam Kelly
Senior Consulting Analyst, L-Soft

The LISTSERV super-list/sub-list mechanism is a feature that allows a sender to post a message to a single super-list and have that message distributed to the subscribers of multiple sub-lists without the message being flagged by LISTSERV as probable spam due to excessive cross-posting. LISTSERV automatically removes any duplicate subscribers among the sub-lists so that each recipient receives a single copy of the message, regardless of their subscription options set on any of the sub-lists. The sub-list feature is also the mechanism employed by LISTSERV Dynamic Query Lists (DQL) to address recipients stored in a database or LDAP directory. Each Dynamic Query is treated as a sub-list, with the same duplicate elimination that LISTSERV does for a regular sub-list.

Prior to LISTSERV 16.0-2014b, the only way to view the recipients of a super-list was to post to the list and check the LISTSERV log file when the message was distributed. (For sites running LISTSERV HPO, even that wasn't an option because the recipient list is truncated in the log file.) The LISTSERV 16.0-2014 level-set introduces the RCPT flag to the REVIEW command, which allows a list owner to view the recipients of a super-list (including a DQL list) without having to post a message to it.

The syntax of the REVIEW command is documented in the LISTSERV 16.0 Site Manager's Manual. The RCPT flag is just an additional flag that can be passed to the REVIEW command. For example, to review the recipients of the SAMPLE super-list interactively through the LISTSERV web interface:

To review the list (including list header) and receive the output via email:

The output will include all list members subscribed directly to the super-list, as well as those subscribed to any of the sub-lists, including those fetched via Dynamic Queries from a DBMS or LDAP data source. This can be especially useful for debugging the output of LDAP queries without having to send mail to the LISTSERV list.

References

LISTSERV Site Manager's Manual 15.13.12: Super-Lists and Sub-Lists
LISTSERV Advanced Topics Guide Section 8: Dynamic Queries
LISTSERV List Owner's Manual Appendix A: LISTSERV Commands

Subscribe to LISTSERV at Work.

© L-Soft 2014. All Rights Reserved.