The device specific feedback information in the file information data structure
starts at position 367 in the INFDS, and contains input/output feedback information
specific to a device.
The length of the INFDS when device specific feedback information is required,
depends on two factors: the device type of the file, and on whether DISK files
are keyed or not. The minimum length is 528; but some files require a longer
INFDS.
For WORKSTN files, the INFDS is long enough to hold the device-specific
feedback information for any type of display or ICF file starting at position
241. For example, if the longest device-specific feedback information requires
390 bytes, the INFDS for WORKSTN files is 630 bytes long (240+390=630).
For externally described DISK files, the INFDS is at least long enough
to hold the longest key in the file beginning at position 401.
More information on the contents and length of the device feedback for
database file, printer files, ICF and display files can be found in the iSeries Information Center database and file systems category.
The contents of the device specific input/output feedback area of the file
are copied by RPG to the device specific feedback section of the INFDS:
If the presence of a POST operation affects the file:
only after a POST for the file.
Otherwise:
after each I/O operation, if blocking is not
active for the file.
after the I/O request to data management to get or put a block of data,
if blocking is active for the file.
Notes:
After each keyed input operation, only the key fields will be updated.
After each non-keyed input operation, only the relative record number
will be updated.