Let's not confuse DEVICE classes with VOLUME classes. They are not at all
the same. AFAIK the only way to get an accurate list of disk VOLUME class
names is with VOLUTIL.

A disk can have a DEVICE class and/or a VOLUME class (and they can even be
the same.) The :SHOWDEV command shows DEVICE classes  that cannot be used
one a FILE/BUILD command to determine the VOLUME class a file will reside
on. Here is an example. The DEVICE class SPOOL exists, but the VOLUME class
SPOOL does not.

:showdev spool
 LDEV     AVAIL         OWNERSHIP         VOLID         DEN   ASSOCIATION

    1     DISC          N/A
    2     DISC          N/A

:volutil "showset mpexl_system_volume_set classes"
Volume Utility A.02.00, (C) Hewlett-Packard Co., 1987. All Rights Reserved.
volutil: showset mpexl_system_volume_set classes

Volume-class name:                       Index:
-----------------                        -----

  DISC                                      1


:build foo;dev=*SPOOL     <<build the file on VOLUME class SPOOL>>
                ^
Unknown device class. (CIERR 344)

So there needs to be a distinction between the two. The original question
was how to show all VOLUME classes on the system. The discussion seems to
have split into both VOLUME and DEVICE class threads and I wanted to address
the difference between the two.

I am not a big advocate of volume classes, but if I did use them I could see
the benefit of a

  :SHOWVOLCLASS [volumesetname]

command that would list all classes defined within a volume set. In the
meantime Stan and Mark supplied methods to roll your own script.

Also note that the text for CIERR 344 listed above says 'Unknown device
class' Shouldn't that read 'Unknown volume class'?

Doug.

Doug Werth                             Beechglen Development Inc.
[log in to unmask]                               Cincinnati, Ohio