Guardian Procedure Calls Reference Manual

- 4096 bytes (approximately four gigabytes), or a partition size greater than 2**31 bytes
(two gigabytes).
• For unstructured files on a disk device other than a legacy device with 514-byte sectors
3
, both
primary-extent-size and secondary-extent-size must be divisible by 14.
When you create an unstructured disk file that has no secondary partitions, if you specify file
extents that are not divisible by 14 in the CREATE call, the extents are automatically rounded
up to the next multiple of 14, and the specified MAXEXTENTS is lowered to compensate.
CREATE does not return an error code to indicate this change. This change is visible only if
you call FILE_GETINFOLIST_ to verify the extent size and the MAXEXTENTS attributes.
However, when you create an unstructured disk file that has one or more secondary partitions,
extent sizes that are multiples of 14 pages must be explicitly specified in the CREATE call.
Otherwise, the CREATE returns error code 1099 to the caller.
• Altering file security
The file is created with the caller's process file security that can be examined and set with the
PROCESSFILESECURITY procedure. After a file has been created, its file security can be altered
by opening the file and issuing the appropriate SETMODE and SETMODENOWAIT functions.
• Odd unstructured files
An odd unstructured file permits reading and writing of odd byte counts and positioning to
an odd byte address.
When creating unstructured files, the value passed for file-type.<12> determines how all
subsequent reading, writing, and positioning operations to the file work.
If file-type.<12> is passed as 1 and file-type.<13:15> is all zeros, an odd unstructured
file is created.
If file-type.<12> is passed as 1, the values of record-specifier, read-count, and
write-count are all interpreted exactly; for example, a write-count or read-count
of 7 transfers exactly 7 bytes.
• Even unstructured files
If file-type.<13:15> is passed to CREATE and is all zeros (specifying an unstructured
file), and file-type.<12> is 0, then an even unstructured file is created.
If file-type.<12> is passed as 0, the values of read-count and write-count are each
rounded up to an even number before the operation begins; for example, a write-count
or read-count of 7 is rounded up to 8, and 8 bytes are transferred.
A file must be positioned to an even byte address; otherwise, FILEINFO or FILE_GETINFO_
returns a file-system error (bad address).
If you use the FUP CREATE or the TACL CREATE command to create the file, it creates an even
unstructured file by default.
• Insertion-ordered alternate keys
All of the non-unique alternate keys of a file must have the same duplicate key ordering attribute.
That is, a file may not have both insertion-ordered alternate keys and standard (duplicate
ordering by primary key) non-unique alternate keys. An insertion-ordered alternate key cannot
share an alternate-key file with other keys of different lengths, or with other keys which are
not insertion-ordered.
The CREATE procedure returns file error 46 if the rules of usage for insertion-ordered alternate
keys are violated.
When an alternate-key record is updated, the timestamp portion of the key is also updated.
Alternate-key records are updated only when the corresponding alternate-key field of the
primary record is changed.
3. Devices with 514-byte sectors are not used on TNS/E systems.
236 Guardian Procedure Calls (C)