Guardian Procedure Calls Reference Manual

Returned Value
INT
A file-system error code that indicates the outcome of the call.
22
• The address of a parameter is extended, but no segment is in use at the time of the call or the segment in
use is invalid.
• The address of a parameter is extended, but it is an absolute address and the caller is not privileged.
• The file system cannot use the user's segment when needed.
Considerations
• EpTAL callers must set toggle
EpTAL callers must set the toggle _64BIT_CALLS before sourcing the
FILE_WRITEUPDATEUNLOCK64_ procedure section from EXTDECS.
• Familar semantics
Unless otherwise described, the semantic behavior of FILE_WRITEUPDATEUNLOCK64_ is the
same as that of WRITEUPDATEUNLOCKX.
• Nowait I/O and FILE_WRITEUPDATEUNLOCK64_
If FILE_WRITEUPDATEUNLOCK64_ is called on a file opened for nowait I/O, then the operation
must be completed by calling either FILE_AWAITIO64_ or FILE_COMPLETEL_.
For files audited by the Transaction Management Facility (TMF), FILE_AWAITIO64_ or
FILE_COMPLETEL_ must be called to complete the FILE_WRITEUPDATEUNLOCK64_ operation
before ENDTRANSACTION or ABORTTRANSACTION is called.
WARNING! When using nowait file I/O, data corruption might occur if the READ or WRITE
buffers are modified before the FILE_AWAITIO64_ or FILE_COMPLETEL_ that completes the
call. The buffer space must not be freed or reused while the I/O is in progress.
Do not change the contents of the data buffer between the initiation and completion of a
nowait write operation. This is because a retry can copy the data again from the user buffer
and cause the wrong data to be written. Avoid sharing a buffer between a write and another
I/O operation because this creates the possibility of changing the contents of the write buffer
before the write is completed.
• Random processing and FILE_WRITEUPDATEUNLOCK64_
For key-sequenced, relative, and entry-sequenced files, random processing implies that a
designated record must exist. This means positioning for FILE_WRITEUPDATEUNLOCK64_ is
always to the record described by the exact value of the current key and current-key specifier.
If such a record does not exist, the call to FILE_WRITEUPDATEUNLOCK64_ is rejected with
file-system error 11 (record does not exist).
• Unstructured files—pointers unchanged
For unstructured files, data is written in the position indicated by the current-record pointer. A
call to FILE_WRITEUPDATEUNLOCK64_ for an unstructured file typically follows a call to
FILE_SETPOSITION_ (or POSITION) or FILE_READUPDATE64_. The current-record and
next-record pointers are not changed by a call to FILE_WRITEUPDATEUNLOCK64_ .
• How FILE_WRITEUPDATEUNLOCK64_ works
The record unlocking performed by FILE_WRITEUPDATEUNLOCK64_ functions in the same
manner as FILE_UNLOCKREC64_.
FILE_WRITEUPDATEUNLOCK64_ Procedure 545