Guardian Procedure Calls Reference Manual (G06.25+)

Guardian Procedure Calls (D-E)
Guardian Procedure Calls Reference Manual—522629-013
4-62
DEVICE_GETINFOBYLDEV_ Procedure
(Superseded on G-series Releases)
error-detail output
INT .EXT:ref:1
for some returned errors, contains additional information. See
error, earlier in
this subsection.
Considerations
•
I/O process status
The physical information that is returned in
primary-info and backup-info
includes a status field (see “Device Attributes and Value Representations,” later in
this subsection). This field contains a file-system error number that indicates the
result of the request for information from the I/O process.
It is possible for DEVICE_GETINFOBYLDEV_ to return an
error value of 0
(information successfully returned) while the IOP reports an error in the status field.
In that case, the
error value of 0 indicates that communication with the IOP was
successful, while the IOP status value reflects the validity of the returned
information.
•
Searching logical devices
To perform a search of logical devices, you must specify
options.<15> = 1.
DEVICE_GETINFOBYLDEV_ searches logical device numbers starting with the
number immediately following
ldevnum. Information is returned for the next
device found.
To search all logical devices, set the initial value of
ldevnum to -1; for each
iteration of the search, update
ldevnum to the logical device number of the last
device for which information was returned. The logical device number of a device
is returned in
logical-info (see “Device Attributes and Value Representations,”
later in this subsection).
When
match-type is supplied (in combination with options.<14> equal to 1), or
when
match-subtype is supplied (in combination with options.<13> equal to
1), the search returns information only for a device of the specified type or subtype.
match-type and match-subtype can be used together; in that case, a device
must match both the specified type and subtype to be selected by the search.
When a search can find no more devices, an
error value of 4 is returned and
error-detail contains 19 (no more devices).