On 6/10/2005 1:42 PM, Brett Watts wrote:
> Hello,
>  
> Being a new Listserv administrator, I was wondering if there was a way
> set up a list so that those subscribedto a list, could not unsubscribe
> themselves.
>  
> The situation is that we have announce mailing lists that we to
> subscribe all personnel so we can contact them with important
> information but we don't want them to be able to unsubscribe themselves
> off the lists and miss the information. 
>  
> Any information would helpful.  Thank you in advance for your help.
>

Whenever this question arises, people offer suggestions such as locking the
list to prevent changes, or periodically refreshing the list to ensure that
everyone who should be subscribed is subscribed. These and other tricks are
not foolproof, and some of them introduce other challenges.

It is possible to configure a list to prevent subscribers from leaving,
however, it requires the installation of a list exit. A list exit is a
custom program which the site administrator (LISTSERV postmaster) installs
on the LISTSERV server. The installation of a list exit also requires
changes to the site configuration file. These changes can be made only by
the site administrator. The use of a list exit for a given list requires
changes to the list header by the site administrator. The list owner is not
authorized to make the required changes.

We have a list exit which will prevent a subscriber from leaving a list, and
one which will prevent a subscriber from leaving a list or changing his/her
subscriber option settings. We are running LISTSERV 1.8e on Solaris 2.8, and
the list exits are written in perl. The exits were originally written for
LISTSERV 1.8d, also on Solaris 2.8. No changes were needed when we upgraded
from 1.8d to 1.8e. I have not tested the exits with any other versions of
LISTSERV or on any other OS platforms. I am willing to share the code with
other site administrators, but I do not have the time to help port them to
other OS platforms or languages. If you are a LISTSERV site administrator
and want copies of these exits, contact me off-list.

--
Paul Russell
Senior Systems Administrator
OIT Messaging Services Team
University of Notre Dame