VMS Help SET, VOLUME, Qualifiers  *Conan The Librarian (sorry for the slow response - running on an old VAX)

1 - /ACCESSED

       /ACCESSED[=n]

    Requires OPER (operator) privilege.

    Specifies the number of directories to be maintained in system
    space for ready access. You can specify a value n in the range
    of 0 to 255. If you specify the qualifier /ACCESSED and omit
    the number of directories, a default value of 3 is used. If you
    specify a value greater than the current value, the new value is
    effective immediately; otherwise, the new value is not effective
    until the next time the volume is mounted.

2 - /DATA_CHECK

       /DATA_CHECK[=(option[,...])]

    Defines a default for data check operations following all read
    and write operations to the specified volume. (If you do not
    specify the /DATA_CHECK qualifier, no checks are made.) Possible
    keywords are as follows:

    READ    Performs checks following all read operations.
    WRITE   Performs checks following all write operations (default).

3 - /ERASE_ON_DELETE

       /ERASE_ON_DELETE
       /NOERASE_ON_DELETE (default)

    Determines whether the space occupied by a file is overwritten
    with a system-specified pattern when a file on the volume is
    deleted.

4 - /EXTENSION

       /EXTENSION[=n]

    Specifies the number of blocks to be used as a default extension
    size for all files on the volume. You can specify a value n in
    the range of 0 to 65,535. If you specify the /EXTENSION qualifier
    without specifying a value, a default value of 0 (the OpenVMS RMS
    default) is used.

    For example, during an update operation, the extension default
    is used when a file increases to a size greater than its initial
    default allocation.

5 - /FILE_PROTECTION

       /FILE_PROTECTION=(ownership[:access][,...])

    Sets the default protection to be applied to all files on the
    specified disk volume. Specify the ownership parameter as system
    (S), owner (O), group (G), or world (W) and the access parameter
    as read (R), write (W), execute (E), or delete (D). A null access
    specification means no access.

                                   NOTE

       This attribute is not used while the volume is in use on an
       OpenVMS system, but the attribute is provided to control
       the process use of the volume on RSX-11M systems. The
       OpenVMS system always uses the default file protection;
       the protection can be changed with the DCL command SET
       PROTECTION/DEFAULT.

6 - /HIGHWATER_MARKING

       /HIGHWATER_MARKING
       /NOHIGHWATER_MARKING

    Determines whether the file highwater mark (FHM) volume attribute
    is set. The FHM attribute guarantees that a user cannot read data
    that was not written by the user. Applies to Files-11 On-Disk
    Structure Level 2 (ODS-2) and 5 (ODS-5) volumes only.

7 - /LABEL

       /LABEL=volume-label

    Specifies a 1- to 12-character ANSI name to be encoded on the
    volume. The specified label remains in effect until it is changed
    explicitly; dismounting the volume does not affect the label.
    Compaq strongly recommends that a volume label should consist
    only of alphanumeric characters, dollar signs ($),  underscores
    (_),  and hyphens (-).

    If you change the volume label on an OpenVMS system disk, you
    should also update the POLYCENTER Software Installation utility
    database. To accomplish this, use the PRODUCT REGISTER VOLUME
    command to replace the old volume label with the new volume
    label.

                                   NOTE

       Changing the volume label does not change other structures
       that used the original volume label. For example, the
       DISK$labelname logical is not changed nor is the device-lock
       name that is kept internally by OpenVMS. As a result, if
       you attempt to access another disk that has the same volume
       label as the original volume of this device, you may get
       error messages such as the following: "%MOUNT-F-VOLALRMNT,
       another volume of same label already mounted".

       Compaq recommends that, if you change a disk volume label,
       you also dismount and remount the disk on all nodes in the
       cluster so that the names and locks are consistent.

8 - /LOG

       /LOG
       /NOLOG (default)

    Determines whether the volume specification of each volume is
    displayed after the modification.

9 - /MOUNT_VERIFICATION

       /MOUNT_VERIFICATION
       /NOMOUNT_VERIFICATION

    Determines whether mount verification is enabled. Mount
    verification prevents interruption to user input/output
    operations and notifies the operator of problems with the disk.

10 - /OWNER_UIC

       /OWNER_UIC[=uic]

    Sets the owner user identification code (UIC) of the volume
    to the specified UIC. The default UIC is that of the current
    process. Brackets ([])  are required around the UIC. Specify
    the UIC by using standard UIC format as described in the OpenVMS
    Guide to System Security.

11 - /PROTECTION

       /PROTECTION=(ownership[:access][,...])

    Specifies the protection to be applied to the volume. The
    following rules apply:

    o  Specify the ownership parameter as system (S),  owner (O),
       group (G),  or world (W).

    o  Specify the access parameter as read (R),  write (W), create
       (C),  or delete (D).

    The default protection is all types of access by all categories
    of user.

12 - /REBUILD

       /REBUILD[=FORCE]

    Recovers caching limits for a volume that was dismounted
    improperly. If a disk volume was dismounted improperly (such
    as during a system failure), and was then remounted with the
    MOUNT/NOREBUILD command, you can use SET VOLUME/REBUILD to
    recover the caching that was in effect at the time of the
    dismount. The FORCE option forces the disk to be rebuilt
    unconditionally, thus updating the free block count in the disk
    volume's lock value block.

13 - /RETENTION

       /RETENTION=(min[,max])

    Specifies the minimum and maximum retention times to be used by
    the file system to determine the expiration date for files on
    the volume. When a file is created, its expiration date is set
    to the current time plus the maximum time. Each time the file is
    accessed, the current time is added to the minimum time. If the
    sum is greater than the expiration date, a new expiration date is
    computed.

    If you omit the maximum value, a default value that
    is the smaller of (2 x min) or (min + 7) days is
    used. For example, /RETENTION=3- is the same as
    /RETENTION=(3-,6-), while /RETENTION=10- is the same as
    /RETENTION=(10-,17-).

    The command SET VOLUME/RETENTION=0 disables retention times on
    the volume.

14 - /STRUCTURE_LEVEL

       /STRUCTURE_LEVEL=n

    Sets the structure level of the volume. Use the value 5 to set
    the volume to ODS-5.

    When the /STRUCTURE_LEVEL qualifier is used with other
    qualifiers, the volume structure level is set prior to the other
    qualifiers being performed.

    You cannot use the SET VOLUME command to change a volume from
    ODS-5 to ODS-2. To reset a volume to ODS-2, refer to instructions
    in the OpenVMS Guide to Extended File Specifications.

                                   NOTE

       Compaq does not support creating the system disk as (or
       changing it to) an ODS-5 volume.

    Refer to the OpenVMS Guide to Extended File Specifications for
    further information.

15 - /SUBSYSTEM

       /SUBSYSTEM
       /NOSUBSYSTEM

    Enables the processing of subsystem ACEs. Requires the SECURITY
    privilege. By default, the disk from which you boot has protected
    subsystems enabled but other disks do not. For further details on
    subsystems, refer to the OpenVMS Guide to System Security.

16 - /UNLOAD

       /UNLOAD (default)
       /NOUNLOAD

    Specifies whether the volume is unloaded (spun down) when the DCL
    command DISMOUNT is entered.

17 - /USER_NAME

       /USER_NAME[=user-name]

    Specifies a user name of up to 12 alphanumeric characters to be
    recorded on the volume. The default name is the current process
    user name.

18 - /WINDOWS

       /WINDOWS[=n]

    Specifies the number of mapping pointers to be allocated for file
    windows. The value of n can be from 7 to 80; the default value is
    7.

19 - /WRITETHROUGH

       /WRITETHROUGH
       /NOWRITETHROUGH

    This qualifier only affects applications such as PATHWORKS that
    can request deferred writes to file headers. You use it to
    control whether these applications can use the deferred write
    feature.

    Use /NOWRITETHROUGH to allow these applications to use the
    deferred write feature. When one of these applications explicitly
    requests a deferred write when updating a file header, control
    returns to the application when the I/O request has been queued;
    the application does not have to wait until the data is on disk.

    Note that although the SHOW DEVICES/FULL command shows the volume
    status as write-back caching enabled, the extended file cache
    (XFC) will still be in write-through mode.

    Use /WRITETHROUGH to disable the deferred write feature, so that
    no applications can use it. The SHOW DEVICES/FULL command shows
    the volume status as write-through caching enabled.

    The deferred write feature is not available on Files-11 ODS-1
    volumes.