Guardian Programming Reference Summary for C

SETMODE Operations
Guardian Programming Reference Summary for C—522630-001
11-21
141 DP2 disk file: Enable/disable large transfers
param1
= 1 enable large transfers
= 0 disable large transfers (this is the default value when the file is opened.)
The param2 parameter is not used with function 141.
last-params [0] contains the previous setting of the large transfer mode flag.
last-params [1] if param1 is 1, this contains the value of the file's broken
flag after the cache has been flushed. if param1 is 0, this contains a 0.
SETMODE 141 is valid only for DP2 disk files. When enabled by a SETMODE
141 (or SETMODENOWAIT 141), a read or write operation can transfer up to
56K bytes of data to a DP2 disk file if the operation is local or over a FOX
connection, or up 32K bytes if it is through Expand. Large transfer operations
are allowed on remote DP2 files if the DP2 disk process is at release level C00
or higher.
If this SETMODE function is waited and any nowait I/O operations are
outstanding at the time SETMODE is called, the SETMODE is not done. The
condition code is set to CCL and error 27 is returned.
When this SETMODE function is issued with param1 set to 1, DP2 flushes and
removes all blocks for the file from its cache. This ensures that any updates
done by the user before the SETMODE are written to disk.
The file must have been opened with the unstructured access option specified,
even if the file is unstructured. There is no support for alternate-key files or
partitions. Because the file is opened for unstructured access, secondary
partitions and alternate-key files are not opened.