HP 3000 Manuals HP 3000 Manuals
FFILEINFO
(changed)
You can retrieve items of information by specifying up to five
itemnum/item pairs in the parameter of FFILEINFO. A number of the item
values are changed in MPE XL:
No. Item Value
----------------------------------------------------------------------------------------
6 For standard disc files, this returns the logical device number where the
device's label resides. This may not be the same logical device that
contains the file's data.
13 Indicates buffered physical count of data blocks transferred. If file was
opened using other than buffered access (nobuf), this figure will not be
meaningful.
44 The number returned here indicates the number of disc extents currently
allocated to the file. Extent allocation is in the order in which they are
accessed, not in physical order, as in MPE V/E.
50 Returns the logical device number (ldev) of the device associated with the
file.
NOTE In the preceding discussion, the term standard disc file refers to
a file that is not a KSAM, RIO, circular, or message file. For
further discussion of file types, see Accessing Files Programmer's
Guide (32650-90017).
New Item Values
Because of the change to 32-bit addressing, it is now possible to get
values for record size (Item 4), block size (Item 14), and extent size
(Item 15, described below) that are greater than those allowed in MPE
V/E. If the MPE V/E limit is exceeded for any of those three values, a
zero (0) is returned in the appropriate item. Three new items have been
added that will return the larger values available for standard disc
files: Items 67, 68, and 69. (Note that Item 69 exists for
compatibility reasons only. See the description of Items 15 and 16
below.)
The following new values are returned only for standard disc files:
Item 62 File lockword
Item 63 Unique File Identity (UFID) (NM only)
Item 64 File virtual address
Item 66 Global Unique File Descriptor (GUFD) pointer (NM only)
Item 67 MPE XL record size (32-bit unsigned integer)
Item 68 MPE XL block size (32-bit unsigned integer)
Item 69 MPE XL extent size (32-bit unsigned integer)
Item 74 File label virtual address (64-bit address) (NM only)
Item 75 Hardware path (32-byte character array) (NM only)
Item 76 Volume Restriction (34-byte character array) (NM only)
Item Values No Longer Valid
Because of the changed system architecture in MPE XL, some values
returned by FFILEINFO are no longer meaningful for standard disc files.
The items have been retained for compatibility reasons, and always return
a zero:
Item 19 File label disc sector address
Item 40 Disc device status
In the MPE XL file system, disc file extents may be fixed or variable in
length with no practical limit on their numbers. Extent values are
determined by run-time access heuristics and available space. If a user
specifies extent size = 0, or maximum number of extents = 0 at file
creation, then size and number of extents are determined by the system.
In that case the following item values are calculated using MPE defaults,
and do not reflect actual values:
Item 15 Extent size
Item 16 Maximum # of extents
Hardcoded Item Values
Certain item values have been hardcoded because MPE XL does not
distinguish between the devices currently supported. These items and
their values are:
For standard disc files only:
Item 5 Device type/subtype (returns type=3, subtype=8)
Item 41 Device type (returns type=3)
Item 42 Device subtype (returns subtype=8)
For all disc files:
Item 7 Hardware device address (returns drt=8, unit=0)
Item 47 DRT number (returns drt=8)
Item 48 Device unit number (returns unit=0)