Open System Services System Calls Reference Manual (G06.28+, H06.05+)

System Functions (s and S) SPT_WRITEUPDATEX(2)
the odd unstructured attribute is not set when the
file is created, the value of write_count is
rounded up to an even value before the
SPT_WRITEUPDATEX() call is executed.
You set the odd unstructured attribute with the
Guardian FILE_CREATE_,
FILE_CREATELIST_, or CREATE procedure,
or with the File Utility Program (FUP) SET and
CREATE commands.
Structured files
Calling SPT_WRITEUPDATEX() after KEYPOSITION
If the call to SPT_WRITEUPDATEX()
immediately follows a call to the Guardian
KEYPOSITION procedure in which a
nonunique alternate key is specified as the
access path, the SPT_WRITEUPDATEX()
call fails. A subsequent call to the Guardian
FILE_GETINFO_ or FILEINFO procedure
shows that Guardian file-system error 46
(invalid key) occurred. However, if an inter-
mediate call to SPT_READX( ) or
SPT_READLOCKX() is performed, the call to
SPT_WRITEUPDATEX() is permitted
because a unique record is identified.
Specifying write_count for entry-sequenced files
For entry-sequenced files, the value of
write_count must match exactly the write_count
value specified when the record was originally
inserted into the file.
Changing the primary-key of a key-sequenced record
An update to a record in a key-sequenced file
cannot alter the value of the primary-key field.
To change the primary-key field, you must
delete the old record
(SPT_WRITEUPDATEX() with write_count =
0 [zero]) and insert a new record with the key
field changed (SPT_WRITEX()).
Current-state indicators after SPT_WRITEUPDATEX()
After a successful SPT_WRITEUPDATEX()
call, the current-state indicators remain
unchanged.
The buffer and count transferred can be in the user stack or in an
extended data segment. The buffer and count transferred cannot
be in the user code space.
527186-007 Hewlett-Packard Company 7−359