>to write a program which uses it to allow the postmaster to send
>a command to all remote LISTSERVs requesting that any of the listed
>userids from his/her node be deleted.  If that seems to open too
>big a security hole (i.e. can someone fake being the postmaster?)
>then it could at least generate a letter to all of the remote
>postmasters requesting that it be done.  The remote postmaster could
>then verify the request according to local security conventions.
A slight variation which would be much easier on the network (and perhaps
build on existing tools in LISTSERV?) would be a command to instruct
the ListServ network to forward a list of all userids that are from their
node and on some list (and the name of the list(s)). Since ListServ
already knows how to forward commands to all other ListServes the
postmaster would only need to know the name of one ListServ. The delete
process could then be done thru normal mechanisms (e.g. send a request
to the list's owner of all userids to be deleted, already knowing that
the userid is really on the list). This avoids having to broadcast a
list of userids that MIGHT be on some list (could be several thousand
at a time for sites such as ours) in favor of returning just the list
that really is on a list. In addition, each piece of this (getting a
list of all userids from ListServ and deletion of specific userids)
is useful in itself.