Guide to OpenVMS File Applications

Document revision date: 19 July 1999

Guide to OpenVMS File Applications

Contents

Index

9.2.4 Record Access Options

You can specify the record access for a record stream as sequential, random by key or record number, or random by RFA. (See Section 8.1.) The selected record access can be changed for each record processing operation. These options can be set using the RAB$B_RAC field, values RAB$C_SEQ, RAB$C_KEY, and RAB$C_RFA.

9.2.5 Options for Adding Records

When adding records to a file, consider the open and connection options in the following table:

Option Description

Default extension
quantity ¹ See Section 9.2.3.

Deferred-write ¹ See Section 9.2.3.

End-of-file After the record stream is connected, the record context is positioned to the end of the file.

FDL: CONNECT END_OF_FILE
RMS: RAB$L_ROP RAB$V_EOF

Retrieval window
size ¹ See Section 9.2.3.

Revision data The revision date and time and the revision number can be specified to be a value other than the actual revision date and time and revision number when the file is closed. These options must be set while the file is open and thus cannot be set using FDL.

FDL: Does not apply
RMS: Revision Date and Time XAB

Truncate on Put ¹ When using sequential record access for sequential files only, the record to be written is the last record in the file, and RMS truncates the file just beyond that record.

FDL: CONNECT TRUNCATE_ON_PUT
RMS: RAB$L_ROP RAB$V_TPT

Update-if ¹ If you set this option and your program tries to replace an existing record while adding records randomly to a file, RMS modifies the existing record instead of replacing it. When using this option for indexed files, note that the file must not allow duplicates for the primary key. Use this option carefully with a shared file (see Section 8.1).

FDL: CONNECT UPDATE_IF
RMS: RAB$L_ROP RAB$V_UIF

Write-behind ¹ See Section 9.2.3.

Option	Description
Default extension quantity ¹	See Section 9.2.3.
Deferred-write ¹	See Section 9.2.3.
End-of-file	After the record stream is connected, the record context is positioned to the end of the file. FDL: CONNECT END_OF_FILE RMS: RAB$L_ROP RAB$V_EOF
Retrieval window size ¹	See Section 9.2.3.
Revision data	The revision date and time and the revision number can be specified to be a value other than the actual revision date and time and revision number when the file is closed. These options must be set while the file is open and thus cannot be set using FDL. FDL: Does not apply RMS: Revision Date and Time XAB
Truncate on Put ¹	When using sequential record access for sequential files only, the record to be written is the last record in the file, and RMS truncates the file just beyond that record. FDL: CONNECT TRUNCATE_ON_PUT RMS: RAB$L_ROP RAB$V_TPT
Update-if ¹	If you set this option and your program tries to replace an existing record while adding records randomly to a file, RMS modifies the existing record instead of replacing it. When using this option for indexed files, note that the file must not allow duplicates for the primary key. Use this option carefully with a shared file (see Section 8.1). FDL: CONNECT UPDATE_IF RMS: RAB$L_ROP RAB$V_UIF
Write-behind ¹	See Section 9.2.3.

¹Indicates an option that can be specified for each record-processing operation. For more information, see Section 9.3.

9.2.6 Options for Data Reliability

The following table lists the run-time file open options that apply to data reliability:

Option Description

Read-check Specifies that transfers from volumes are to be checked by a read-compare operation, which effectively doubles the amount of disk I/O performed. This option is not available for all devices (see the OpenVMS Record Management Services Reference Manual.)

FDL: FILE READ_CHECK
RMS: FAB$L_FOP FAB$V_RCK

Write-check Specifies that transfers to volumes are to be checked by a read-compare operation, which effectively doubles the amount of disk I/O performed. This option is not available for all devices (see the OpenVMS Record Management Services Reference Manual).

FDL: FILE WRITE_CHECK
RMS: FAB$L_FOP FAB$V_WCK

Option	Description
Read-check	Specifies that transfers from volumes are to be checked by a read-compare operation, which effectively doubles the amount of disk I/O performed. This option is not available for all devices (see the OpenVMS Record Management Services Reference Manual.) FDL: FILE READ_CHECK RMS: FAB$L_FOP FAB$V_RCK
Write-check	Specifies that transfers to volumes are to be checked by a read-compare operation, which effectively doubles the amount of disk I/O performed. This option is not available for all devices (see the OpenVMS Record Management Services Reference Manual). FDL: FILE WRITE_CHECK RMS: FAB$L_FOP FAB$V_WCK

9.2.7 Options for File Disposition

The run-time file open options that apply to file disposition are listed in the following table. These options can only be selected while the file is open.

Option Description

Delete on close Deletes the file when it is closed.

FDL: CONNECT DELETE_ON_CLOSE
RMS: FAB$L_FOP FAB$V_DLT

Submit command file Submits a sequential file as a batch command procedure to SYS$BATCH when you close the file.

FDL: FILE SUBMIT_ON_CLOSE
RMS: FAB$L_FOP FAB$V_SCF

Spool on close Prints a sequential file on SYS$PRINT when you close the file.

FDL: FILE PRINT_ON_CLOSE
RMS: FAB$L_FOP FAB$V_SPL

Option	Description
Delete on close	Deletes the file when it is closed. FDL: CONNECT DELETE_ON_CLOSE RMS: FAB$L_FOP FAB$V_DLT
Submit command file	Submits a sequential file as a batch command procedure to SYS$BATCH when you close the file. FDL: FILE SUBMIT_ON_CLOSE RMS: FAB$L_FOP FAB$V_SCF
Spool on close	Prints a sequential file on SYS$PRINT when you close the file. FDL: FILE PRINT_ON_CLOSE RMS: FAB$L_FOP FAB$V_SPL

9.2.8 Options for Indexed Files

The following table lists the run-time options that apply to indexed file processing. For more information about processing indexed files, refer to Section 8.4.3.

Option Description

Fast delete ¹ This option lets you postpone certain internal operations associated with deleting indexed file records until the record is next accessed. This allows records to be deleted rapidly, but it may degrade the performance of processes that read the file later.

FDL: CONNECT FAST_DELETE
RMS: RAB$L_ROP RAB$V_FDL

Key equal or next ¹ If you select this option when locating or reading records, RMS returns the first record with a key value equal to the specified key. If RMS does not find a record with an equal key value, it returns the record with the next higher key value when ascending sort order is specified. When descending sort order is specified, RMS returns the next record with the next lower key value.

FDL: CONNECT KEY_GREATER_EQUAL
RMS: RAB$L_ROP RAB$V_EQNXT

Next key ¹ If you select this option when locating or reading records, RMS returns the record with the next higher key value when you specify ascending sort order. When you specify descending sort order, RMS returns the next record with the next lower key value. If you do not specify either this option or the equal-or-next-key option, RMS tries for a key match.

FDL: CONNECT KEY_GREATER_THAN
RMS: RAB$L_ROP RAB$V_NXT

Key of reference When you process an indexed file with multiple keys, this option permits you to specify which key to use for the current record stream.

FDL: CONNECT KEY_OF_REFERENCE
RMS: RAB$B_KRF

Key buffer ¹ If you select this option when locating or reading records randomly, the specified key buffer must contain the selected record's key.

FDL: None
RMS: RAB$L_KBF

Key size ¹ If you select this option when locating or reading records with a string data-type key, you can specify that only a portion of the key be used to locate the selected record.

FDL: None
RMS: RAB$B_KSZ

Limit key ¹ This option directs RMS, when locating or reading records sequentially, to return an alternate success status if the record key exceeds the specified key.

FDL: CONNECT KEY_LIMIT
RMS RAB$L_ROP RAB$V_LIM

Load buckets ¹ If you select this option when adding records to an index file, RMS uses the fill factor specified when the file was created. By default, RMS fills buckets completely.

FDL: CONNECT FILL_BUCKETS
RMS: RAB$L_ROP RAB$V_LOA

Option	Description
Fast delete ¹	This option lets you postpone certain internal operations associated with deleting indexed file records until the record is next accessed. This allows records to be deleted rapidly, but it may degrade the performance of processes that read the file later. FDL: CONNECT FAST_DELETE RMS: RAB$L_ROP RAB$V_FDL
Key equal or next ¹	If you select this option when locating or reading records, RMS returns the first record with a key value equal to the specified key. If RMS does not find a record with an equal key value, it returns the record with the next higher key value when ascending sort order is specified. When descending sort order is specified, RMS returns the next record with the next lower key value. FDL: CONNECT KEY_GREATER_EQUAL RMS: RAB$L_ROP RAB$V_EQNXT
Next key ¹	If you select this option when locating or reading records, RMS returns the record with the next higher key value when you specify ascending sort order. When you specify descending sort order, RMS returns the next record with the next lower key value. If you do not specify either this option or the equal-or-next-key option, RMS tries for a key match. FDL: CONNECT KEY_GREATER_THAN RMS: RAB$L_ROP RAB$V_NXT
Key of reference	When you process an indexed file with multiple keys, this option permits you to specify which key to use for the current record stream. FDL: CONNECT KEY_OF_REFERENCE RMS: RAB$B_KRF
Key buffer ¹	If you select this option when locating or reading records randomly, the specified key buffer must contain the selected record's key. FDL: None RMS: RAB$L_KBF
Key size ¹	If you select this option when locating or reading records with a string data-type key, you can specify that only a portion of the key be used to locate the selected record. FDL: None RMS: RAB$B_KSZ
Limit key ¹	This option directs RMS, when locating or reading records sequentially, to return an alternate success status if the record key exceeds the specified key. FDL: CONNECT KEY_LIMIT RMS RAB$L_ROP RAB$V_LIM
Load buckets ¹	If you select this option when adding records to an index file, RMS uses the fill factor specified when the file was created. By default, RMS fills buckets completely. FDL: CONNECT FILL_BUCKETS RMS: RAB$L_ROP RAB$V_LOA

¹Indicates an option that can be specified for each record-processing operation. For more information, see Section 9.3.

9.2.9 Options for Magnetic Tape Processing

The run-time file open and close options that apply to magnetic tape processing are listed in the following table:

Option Description

Not end-of-file Use this option when you want to add a record to a location other than at the end of the file.

FDL: FILE MT_NOT_EOF
RMS: FAB$L_FOP FAB$V_NEF

Current position If you select this option when creating a file, the tape is positioned to the location immediately following the most recently closed file.

FDL: FILE MT_CURRENT_POSITION
RMS: FAB$L_FOP FAB$V_POS

Rewind on Open If you select this option, RMS directs that the tape volume be rewound before it opens or creates the file. The rewind-on-open option overrides the current-position option.

FDL: FILE MT_OPEN_REWIND
RMS: FAB$L_FOP FAB$V_RWO

Rewind on Close If you select this option, RMS directs that the tape volume be rewound before it closes the file.

FDL: FILE MT_CLOSE_REWIND
RMS: FAB$L_FOP FAB$V_RWC

Option	Description
Not end-of-file	Use this option when you want to add a record to a location other than at the end of the file. FDL: FILE MT_NOT_EOF RMS: FAB$L_FOP FAB$V_NEF
Current position	If you select this option when creating a file, the tape is positioned to the location immediately following the most recently closed file. FDL: FILE MT_CURRENT_POSITION RMS: FAB$L_FOP FAB$V_POS
Rewind on Open	If you select this option, RMS directs that the tape volume be rewound before it opens or creates the file. The rewind-on-open option overrides the current-position option. FDL: FILE MT_OPEN_REWIND RMS: FAB$L_FOP FAB$V_RWO
Rewind on Close	If you select this option, RMS directs that the tape volume be rewound before it closes the file. FDL: FILE MT_CLOSE_REWIND RMS: FAB$L_FOP FAB$V_RWC

9.2.10 Options for Nonstandard File Processing

The following table lists the run-time file open options that apply to nonstandard file processing:

Option Description

Non-file-structured Use this option when you want to process data from volumes created on systems other than Compaq systems.

FDL: FILE NON_FILE_STRUCTURED
RMS: FAB$L_FOP FAB$V_NFS

User file open Use this option if you want to use RMS only to open the file and you intend to access the contents of the file using Queue I/O Request system service calls. The system returns the I/O channel number in the FAB$L_STV field.

FDL: FILE USER_FILE_OPEN
RMS: FAB$L_FOP FAB$V_UFO

Option	Description
Non-file-structured	Use this option when you want to process data from volumes created on systems other than Compaq systems. FDL: FILE NON_FILE_STRUCTURED RMS: FAB$L_FOP FAB$V_NFS
User file open	Use this option if you want to use RMS only to open the file and you intend to access the contents of the file using Queue I/O Request system service calls. The system returns the I/O channel number in the FAB$L_STV field. FDL: FILE USER_FILE_OPEN RMS: FAB$L_FOP FAB$V_UFO

9.3 Summary of Record Operation Options

This section briefly describes the options associated with the record retrieval services (Find and Get), the record insertion service (Put), the record modification service (Update), and the record deletion service (Delete).

9.3.1 Record Retrieval Options

The Find and Get services (or the equivalent language statements) can be used to locate and retrieve a record.

The options associated with the Find and Get services are summarized in the following table. These options can be set for each Find or Get service if the program can access the appropriate RAB control block fields. The RAB control block fields are preset by connect-time values or defaults and as a result of previous service calls.

Option Description

Asynchronous record
processing Specifies that record I/O for this record stream is done asynchronously.

FDL: CONNECT ASYNCHRONOUS
RMS: RAB$L_ROP RAB$V_ASY

Do not lock record Directs RMS not to lock the record for ensuing operations.

FDL: CONNECT NOLOCK
RMS: RAB$L_ROP RAB$V_NLK

Key buffer When locating/reading records randomly, the specified key buffer must contain the desired record's key.

FDL: None
RMS: RAB$L_KBF

Key equal or next When locating or reading records, RMS returns the first record with a key value equal to the specified key. If RMS does not find a record with an equal key value, it returns the record with the next higher key value when you specify ascending sort order. When you specify descending sort order, RMS returns the record with the next lower key value.

FDL: CONNECT KEY_GREATER_EQUAL
RMS: RAB$L_ROP RAB$V_EQNXT

Next key When locating or reading records, RMS returns the record with the next higher key value when you specify ascending sort order. When you specify descending sort order, RMS returns the record with the next lower key value.

FDL: CONNECT KEY_GREATER_THAN
RMS: RAB$L_ROP RAB$V_NXT

Key of reference For indexed files with multiple keys, the key of reference specifies which key is used for current record stream.

FDL: CONNECT KEY_OF_REFERENCE
RMS: RAB$B_KRF

Key size When using a string key to locate or read records, you can specify that all or part of the key be used.

FDL: None
RMS: RAB$B_KSZ

Limit key This option directs RMS, when locating or reading records sequentially, to return an alternate success status if the record key exceeds the specified key.

FDL: CONNECT KEY_LIMIT
RMS: RAB$L_ROP RAB$V_LIM

Locate mode Specifies the locate mode, instead of the move mode. Applies to the Get service only.

FDL: CONNECT LOCATE_MODE
RMS: RAB$L_ROP RAB$V_LOC

Lock nonexistent
record Indicates that RMS is to lock the record position at the location of the following record operation, regardless of whether a record exists at that location. Applies only to relative files.

FDL: CONNECT NONEXISTENT_RECORD
RMS: RAB$L_ROP RAB$V_NXR

Lock for read Locks record for reading and allows other readers (but no writers).

FDL: CONNECT LOCK_ON_READ
RMS: RAB$L_ROP RAB$V_REA

Lock for write Locks record for writing and allows other readers (but no writers).

FDL: CONNECT LOCK_ON_WRITE
RMS: RAB$L_ROP RAB$V_RLK

Manual locking Allows you to control record locking and unlocking manually.

FDL: CONNECT MANUAL_LOCKING
RMS: RAB$L_ROP RAB$V_ULK

Read ahead Improves performance at the expense of additional memory for I/O buffers. For sequential access to sequential files only.

FDL: CONNECT READ_AHEAD
RMS: RAB$L_ROP RAB$V_RAH

Read regardless Reads the specified record regardless of whether it is locked by another user.

FDL: CONNECT READ_REGARDLESS
RMS: RAB$L_ROP RAB$V_RRL

Record access Specifies the way records are accessed: sequentially, randomly by key (indexed files), by record number (relative files), or randomly by RFA.

FDL: None
RMS: RAB$B_RAC values,
RAB$C_SEQ, RAB$C_KEY,
RAB$C_RFA

RFA Specifies the address of the desired record when records are accessed randomly by RFA (RAB$B_RAC contains RAB$C_RFA). This value is also returned by Find and Get services regardless of the type record access used.

FDL: None
RMS: RAB$W_RFA

Record header buffer Contains the symbolic address of the record header buffer that contains the fixed portion of a VFC record. Applies to the Get service only.

FDL: None
RMS: RAB$L_RHB

Timeout period If the wait-if-locked option is specified, this option may be specified to specify a timeout period after which an error is returned. The number of seconds is specified by the CONNECT TIMEOUT_PERIOD or RAB$B_TMO field to eliminate a potential deadlock.

FDL: CONNECT TIMEOUT_PERIOD
RMS: RAB$L_ROP RAB$V_TMO and
RAB$B_TMO

User buffer address Specifies the address of the user buffer that receives the record. Applies to the Get service only.

FDL: None
RMS: RAB$L_UBF

User buffer size Specifies the maximum length of the user record buffer. Applies to the Get service only.

FDL: None
RMS: RAB$L_USZ

Wait if locked Specifies that if the record is locked, RMS must wait until it is available; also allows use of the wait-timeout-period option.

FDL: CONNECT WAIT_FOR_RECORD
RMS: RAB$L_ROP RAB$V_WAT

Option	Description
Asynchronous record processing	Specifies that record I/O for this record stream is done asynchronously. FDL: CONNECT ASYNCHRONOUS RMS: RAB$L_ROP RAB$V_ASY
Do not lock record	Directs RMS not to lock the record for ensuing operations. FDL: CONNECT NOLOCK RMS: RAB$L_ROP RAB$V_NLK
Key buffer	When locating/reading records randomly, the specified key buffer must contain the desired record's key. FDL: None RMS: RAB$L_KBF
Key equal or next	When locating or reading records, RMS returns the first record with a key value equal to the specified key. If RMS does not find a record with an equal key value, it returns the record with the next higher key value when you specify ascending sort order. When you specify descending sort order, RMS returns the record with the next lower key value. FDL: CONNECT KEY_GREATER_EQUAL RMS: RAB$L_ROP RAB$V_EQNXT
Next key	When locating or reading records, RMS returns the record with the next higher key value when you specify ascending sort order. When you specify descending sort order, RMS returns the record with the next lower key value. FDL: CONNECT KEY_GREATER_THAN RMS: RAB$L_ROP RAB$V_NXT
Key of reference	For indexed files with multiple keys, the key of reference specifies which key is used for current record stream. FDL: CONNECT KEY_OF_REFERENCE RMS: RAB$B_KRF
Key size	When using a string key to locate or read records, you can specify that all or part of the key be used. FDL: None RMS: RAB$B_KSZ
Limit key	This option directs RMS, when locating or reading records sequentially, to return an alternate success status if the record key exceeds the specified key. FDL: CONNECT KEY_LIMIT RMS: RAB$L_ROP RAB$V_LIM
Locate mode	Specifies the locate mode, instead of the move mode. Applies to the Get service only. FDL: CONNECT LOCATE_MODE RMS: RAB$L_ROP RAB$V_LOC
Lock nonexistent record	Indicates that RMS is to lock the record position at the location of the following record operation, regardless of whether a record exists at that location. Applies only to relative files. FDL: CONNECT NONEXISTENT_RECORD RMS: RAB$L_ROP RAB$V_NXR
Lock for read	Locks record for reading and allows other readers (but no writers). FDL: CONNECT LOCK_ON_READ RMS: RAB$L_ROP RAB$V_REA
Lock for write	Locks record for writing and allows other readers (but no writers). FDL: CONNECT LOCK_ON_WRITE RMS: RAB$L_ROP RAB$V_RLK
Manual locking	Allows you to control record locking and unlocking manually. FDL: CONNECT MANUAL_LOCKING RMS: RAB$L_ROP RAB$V_ULK
Read ahead	Improves performance at the expense of additional memory for I/O buffers. For sequential access to sequential files only. FDL: CONNECT READ_AHEAD RMS: RAB$L_ROP RAB$V_RAH
Read regardless	Reads the specified record regardless of whether it is locked by another user. FDL: CONNECT READ_REGARDLESS RMS: RAB$L_ROP RAB$V_RRL
Record access	Specifies the way records are accessed: sequentially, randomly by key (indexed files), by record number (relative files), or randomly by RFA. FDL: None RMS: RAB$B_RAC values, RAB$C_SEQ, RAB$C_KEY, RAB$C_RFA
RFA	Specifies the address of the desired record when records are accessed randomly by RFA (RAB$B_RAC contains RAB$C_RFA). This value is also returned by Find and Get services regardless of the type record access used. FDL: None RMS: RAB$W_RFA
Record header buffer	Contains the symbolic address of the record header buffer that contains the fixed portion of a VFC record. Applies to the Get service only. FDL: None RMS: RAB$L_RHB
Timeout period	If the wait-if-locked option is specified, this option may be specified to specify a timeout period after which an error is returned. The number of seconds is specified by the CONNECT TIMEOUT_PERIOD or RAB$B_TMO field to eliminate a potential deadlock. FDL: CONNECT TIMEOUT_PERIOD RMS: RAB$L_ROP RAB$V_TMO and RAB$B_TMO
User buffer address	Specifies the address of the user buffer that receives the record. Applies to the Get service only. FDL: None RMS: RAB$L_UBF
User buffer size	Specifies the maximum length of the user record buffer. Applies to the Get service only. FDL: None RMS: RAB$L_USZ
Wait if locked	Specifies that if the record is locked, RMS must wait until it is available; also allows use of the wait-timeout-period option. FDL: CONNECT WAIT_FOR_RECORD RMS: RAB$L_ROP RAB$V_WAT

9.3.2 Put Service Options

The Put service (or equivalent language statement) adds a record to the file.

The options associated with the Put service are summarized in the following table. These options can be set for each Put service if the program can access the appropriate RAB control block fields. The RAB control block fields are preset by connect-time values or defaults and as a result of previous service calls.

Option Description

Asynchronous record
processing Specifies that record I/O for this record stream is done asynchronously.

FDL: CONNECT ASYNCHRONOUS
RMS: RAB$L_ROP RAB$V_ASY

Key buffer When adding records randomly to a relative file, the specified key buffer must contain the desired record's relative record number.

FDL: None
RMS: RAB$L_KBF

Key size When adding records to a relative file using random record access, this field must specify a value of 4 (the default value provided by RMS).

FDL: None
RMS: RAB$B_KSZ

Load buckets When adding records, the buckets fill to the level specified when the file is created. The default is that buckets fill completely before a bucket split occurs.

FDL: CONNECT FILL_BUCKETS
RMS: RAB$L_ROP RAB$V_LOA

Read allowed Allows the locked record being written to be read.

FDL: CONNECT LOCK_ON_WRITE
RMS: RAB$L_ROP RAB$V_RLK

Record access Specifies the way records are added, sequentially according to ascending key value or relative record number, randomly by key (indexed files) or by record number (relative files), or randomly by RFA.

FDL: None
RMS: RAB$B_RAC values,
RAB$C_SEQ, RAB$C_KEY,
RAB$C_RFA

Record header buffer Contains the symbolic address of the record header buffer that contains the fixed portion of a VFC record. Applies to the Get service only.

FDL: None
RMS: RAB$L_RHB

Record buffer
address Specifies the address of the record buffer that contains the record to be written.

FDL: None
RMS: RAB$L_RBF

Record buffer size Specifies the size of the record contained in the record buffer to be written.

FDL: None
RMS: RAB$L_RBZ

Timeout period This option is used with the wait-if-locked option to specify a timeout period after which an error is returned. The number of seconds is specified by the CONNECT TIMEOUT_PERIOD or the RAB$B_TMO field to eliminate a potential deadlock.

FDL: CONNECT TIMEOUT_PERIOD
RMS: RAB$L_ROP RAB$V_TMO and
RAB$B_TMO

Truncate on Put Specifies that the file is truncated at the record being added. Requires sequential record access and only applies to sequential files.

FDL: CONNECT TRUNCATE_ON_PUT
RMS: RAB$L_ROP RAB$V_TPT

Update-if Turns the Put service into an update operation if the record already exists in the file. Care must be taken when using this option with shared files and automatic record locking (see Section 8.1). When using this option with indexed files, note that the file must not allow duplicates for the primary key. This option can only be used when random record access has been specified.

FDL: CONNECT UPDATE_IF
RMS: RAB$L_ROP RAB$V_UIF

Write-behind Improves performance at the expense of additional memory for I/O buffers. Requires sequential record access and only applies to sequential files.

FDL: CONNECT WRITE_BEHIND
RMS: RAB$L_ROP RAB$V_WBH

Option	Description
Asynchronous record processing	Specifies that record I/O for this record stream is done asynchronously. FDL: CONNECT ASYNCHRONOUS RMS: RAB$L_ROP RAB$V_ASY
Key buffer	When adding records randomly to a relative file, the specified key buffer must contain the desired record's relative record number. FDL: None RMS: RAB$L_KBF
Key size	When adding records to a relative file using random record access, this field must specify a value of 4 (the default value provided by RMS). FDL: None RMS: RAB$B_KSZ
Load buckets	When adding records, the buckets fill to the level specified when the file is created. The default is that buckets fill completely before a bucket split occurs. FDL: CONNECT FILL_BUCKETS RMS: RAB$L_ROP RAB$V_LOA
Read allowed	Allows the locked record being written to be read. FDL: CONNECT LOCK_ON_WRITE RMS: RAB$L_ROP RAB$V_RLK
Record access	Specifies the way records are added, sequentially according to ascending key value or relative record number, randomly by key (indexed files) or by record number (relative files), or randomly by RFA. FDL: None RMS: RAB$B_RAC values, RAB$C_SEQ, RAB$C_KEY, RAB$C_RFA
Record header buffer	Contains the symbolic address of the record header buffer that contains the fixed portion of a VFC record. Applies to the Get service only. FDL: None RMS: RAB$L_RHB
Record buffer address	Specifies the address of the record buffer that contains the record to be written. FDL: None RMS: RAB$L_RBF
Record buffer size	Specifies the size of the record contained in the record buffer to be written. FDL: None RMS: RAB$L_RBZ
Timeout period	This option is used with the wait-if-locked option to specify a timeout period after which an error is returned. The number of seconds is specified by the CONNECT TIMEOUT_PERIOD or the RAB$B_TMO field to eliminate a potential deadlock. FDL: CONNECT TIMEOUT_PERIOD RMS: RAB$L_ROP RAB$V_TMO and RAB$B_TMO
Truncate on Put	Specifies that the file is truncated at the record being added. Requires sequential record access and only applies to sequential files. FDL: CONNECT TRUNCATE_ON_PUT RMS: RAB$L_ROP RAB$V_TPT
Update-if	Turns the Put service into an update operation if the record already exists in the file. Care must be taken when using this option with shared files and automatic record locking (see Section 8.1). When using this option with indexed files, note that the file must not allow duplicates for the primary key. This option can only be used when random record access has been specified. FDL: CONNECT UPDATE_IF RMS: RAB$L_ROP RAB$V_UIF
Write-behind	Improves performance at the expense of additional memory for I/O buffers. Requires sequential record access and only applies to sequential files. FDL: CONNECT WRITE_BEHIND RMS: RAB$L_ROP RAB$V_WBH

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