On Fri, 29 May 1998, Ben Parker wrote:
> As someone who has never used AFD/UFI in any environment, perhaps one of the
> more experienced users could tell how you use it and why it's so important/
> useful/necessary?  I know what it stands for but I have no concept of a real
> situation where it would be useful.

Automatic File Distribution/File Update Information (AFD/FUI) provides a
mechanism for a person (a subscriber to either AFD or FUI or both) to be
served a file (AFD) each time the file is updated (modified / changed /
revised / edited) so that the person received the latest version of the
file without having to pay attention; the person remains passive, unlike
the case where a person would actively go look on a www site or ftp
server from time to time to see if anything (the file of interest) has
changed. FUI doesn't serve up the file --it just sends the person a
notice that the file has been updated, and the person can then decide
whether to retrieve the latest version; again, the person is passive
with respect to having to seek out the file to determine whether he has
the latest version.

As I indicated, a person "subscribes" to AFD and/or FUI, just like
subscribing to a list. A person chooses which files are of interest to
him, and is served/notified about updates for only those files.

That's the subscriber side of the picture, in a nutshell. He keeps
himself up-to-the minute by virtue of subscribing to the file, and then
sits back passively awaiting notifications and/or copies of revisions.

From the file author's perspective, ADF/FUI provides a way for an author
to distribute documents (files, as I've been calling them) that are
periodically revised, to "customers" who have expressed an interest in
receiving alerts and/or copies of the latest revisions (by virtue of
becoming subscribers to the file). The document author only has to
install the file (similar to PUTting a LIST or WELCOME or ... file for a
LISTSERV list). Distribution of or notification about the update to the
files subscribers is done by AFD/FUI --the author needn't concern
himself with that chore. The author can even "package" a set of
logically-related files together, so that a person can subscribe to the
package or GET the entire package with one command.

All the above is described in much more succinct (and accurate)
language (typical of traditional LISTSERV :>) in their manuals (in the
VM sections).

Bottom line on ADF/FUI --it's a way for lazy authors and lazy readers to
stay in timely touch with each other. One could simulate ADF/FUI poorly
by creating a new LIST for a file (or package of files, if one also
employs the TOPICS feature of LISTs). People subscribe to the list, SET
TOPICs of interest, and the author posts his files as messages to the
list. Subscriptions can be SET to MAIL or INDEX, which would simulate
the AFD and FUI services, respectively. The bother of setting up LISTs,
especially where lots of files might be involved, is overkill compared
to the AFD/FUI approach.

If you don't author documents that are periodically revised (a "real
situation", Ben) or if you as a reader don't have a need to be kept
current on document revisions (another real situation), then you have no
need for AFD/FUI. If you are not lazy (for me, unreal!) and have lots of
time on your hands (unreal), you don't need AFD/FUI. If you think that
surfing the www is fun (definitely seduced into unreality), you don't
need AFD/FUI.  If you "follow the money", then maybe you won't write
AFD/FUI ports to NT/Unix for your needy and faithful customers (that
seems to be today's reality at LSoft)  :>)

Peter