Updated: 11 December 1998 |
OpenVMS Record Management Utilities Reference
Manual
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The ALLOCATION attribute corresponds to the FAB$L_ALQ field.
The ASYNCHRONOUS attribute corresponds to the ASY option in the RAB$L_ROP field.
The BEST_TRY_CONTIGUOUS attribute corresponds to the CBT option in the FAB$L_FOP field.
If you specify separate areas for the data level and the index levels, you must define separate bucket sizes for each file area; thus, the corresponding attribute in each AREA section overrides this related attribute in the FILE section.
The BUCKET_SIZE attribute corresponds to the FAB$B_BKS field.
The CLUSTER_SIZE attribute is output from the Analyze/RMS_File utility (ANALYZE/RMS_FILE), which returns the actual value of the disk cluster size to EDIT/FDL for use during an Optimize script.
The CONTEXT attribute corresponds to the FAB$L_CTX field.
If there is not enough contiguous space for the file's initial allocation, RMS returns an error.
If you take the default, the system allocates no space for the file.
This attribute corresponds to the CTG option in the FAB$L_FOP field.
The CREATE_IF attribute is valid as input to the Create service only. It overrides the SUPERSEDE (supersede existing file) attribute and corresponds to the CIF option in the FAB$L_FOP field.
When a utility creates a data file from an FDL file, it first attempts to get the file specification from the calling process. If the call includes a full file specification, the utility ignores the DEFAULT_NAME and NAME attributes.
When a process supplies a partial file specification, the invoked utility tries to complete the file specification from the DEFAULT_NAME string. If the calling process does not specify a value for DEFAULT_NAME, the utility uses the RMS defaults.
If the calling process supplies a file specification by using the NAME attribute, the utility uses it. If the NAME attribute includes only a partial file specification, the utility uses it and examines the DEFAULT_NAME attribute for the rest of the file specification.
If the NAME and DEFAULT_NAME attributes together provide only a partial file specification, the utility uses RMS default values to complete the file specification.
For example, if you assign the value WRKD$:.KSM to DEFAULT_NAME, unless you specify otherwise, the created data file specification takes the device name WRKD$ and the file type .KSM.
The NAME and DEFAULT_NAME attributes correspond to the FAB$L_DNA and the FAB$B_DNS fields, respectively.
The DEFERRED_WRITE attribute corresponds to the DFW option in the FAB$L_FOP field. This attribute is not supported for DECnet for OpenVMS operations.
The DELETE_ON_CLOSE attribute corresponds to the DLT option in the FAB$L_FOP field. The default is to ignore this attribute.
The DIRECTORY_ENTRY attribute corresponds to the TMP option in the FAB$L_FOP field.
The EXTENSION attribute corresponds to the FAB$W_DEQ field.
The GLOBAL_BUFFER_COUNT attribute corresponds to the FAB$W_GBC field. This attribute is not supported for DECnet for OpenVMS operations.
The MAX_RECORD_NUMBER attribute corresponds to the FAB$L_MRN field.
When you set the switch to NO, assigning an explicit version number lower than an existing version results in creating a new data file with the lower version number. If you assign an explicit version number that matches an existing version, RMS returns an error.
The MAXIMUM_VERSION attribute corresponds to the MXV option in the FAB$L_FOP field.
The MT_BLOCK_SIZE attribute corresponds to the FAB$W_BLS field.
The MT_CLOSE_REWIND attribute corresponds to the RWC option in the FAB$L_FOP field.
If you do not specify either of the position specifiers (MT_CURRENT_POSITION or MT_OPEN_REWIND), RMS creates the new file at the logical end of the tape. If you specify both position specifiers, the MT_OPEN_REWIND attribute overrides the MT_CURRENT_POSITION attribute.
The MT_CURRENT_POSITION attribute corresponds to the POS option in the FAB$B_FOP field.
This attribute corresponds to the NEF option in the FAB$L_FOP field.
Conversely, if you specify this attribute when you open an existing tape file, RMS rewinds to the beginning of the tape but then proceeds to find the specified file before doing any file operations.
Typically, a user specifies the MT_OPEN_REWIND option to improve efficiency in opening a tape file or to ensure access to the correct file when the tape contains files with duplicate names. ANSI tapes allow named files, but they have no directories and can contain repeated instances of files with the same name.
In the first case, assume the tape has 50 files, is positioned at the fortieth file, and the user wants to access the thirtieth file. If the user specifies MT_OPEN_REWIND to the Open service, RMS rewinds the tape to the first file and then winds the tape forward to the thirtieth file. If the user does not specify MT_OPEN_REWIND, RMS winds the tape forward to the end of the tape. Then, not having found the file, RMS rewinds the tape to the first file and proceeds to wind the tape forward to the thirtieth file.
In the second case, assume a tape has two files named X.DAT and is positioned between the two files. Assume further that the user wants to access the first file named X.DAT. If the user does not specify MT_OPEN_REWIND, RMS winds forward until it finds the second file and opens it, instead of opening the desired file. Conversely, if the user does specify MT_OPEN_REWIND, RMS rewinds the tape and then winds forward until it finds and opens the first file named X.DAT.
The MT_OPEN_REWIND option takes precedence over the MT_CURRENT_POSITION option and corresponds to the RWO option in the FAB$L_FOP field.
This attribute corresponds to the XAB$B_MTACC field and is not supported for DECnet for OpenVMS operations.
This attribute corresponds to the FAB$L_FNA and the FAB$B_FNS fields.
On Alpha systems, if you have implemented the on-disk-structure level 5 (ODS-5) volume structure of extended file specifications, you can name a file using the 8-bit ISO Latin-1 or 16-bit Unicode (UCS-2) character sets. You can also have a file name exceed the traditional 39.39 character limit to a maximum of 255 characters.
The default is SEQUENTIAL.
This attribute corresponds to the FAB$B_ORG field.
This attribute corresponds to the OFP option in the FAB$L_FOP field.
octal-group-number,octal-user-number |
For example, OWNER [12,322] indicates that the person in group 12 with the user number 322 is the owner of the data file.
This attribute corresponds to the XAB$W_GRP and the XAB$W_MBM fields.
If you also set DELETE_ON_CLOSE to YES, the file is deleted after it is printed.
This attribute corresponds to the SPL option in the FAB$L_FOP field.
The syntax for encoding protection may take either of the following forms:
(SYSTEM=code,OWNER=code,GROUP=code,WORLD=code) |
(SYSTEM:code,OWNER:code,GROUP:code,WORLD:code) |
You must enclose the protection specification in parentheses and you have the option of using either the equal sign (=) or a colon (:) to separate each keyword from its associated code value.
By default, RMS assigns the file the default protection for the current process. To see the default protection for the current process, use the DCL command SHOW PROTECTION.
To deny a user class a specific access level, omit the access level from the code. To deny a user class all access levels, omit the user class keyword from the protection specification. For example, the following protection specification gives all access levels to user class System and user class Owner, read access to user class Group, and no access levels to user class World:
(System=RWED,Owner=RWED,Group=R) |
This attribute corresponds to the XAB$W_PRO field.
When you activate the switch, transfers from disk volumes are followed by read-compare operations. This double check increases the likelihood that the system will catch data errors; however, it also increases disk overhead.
Activating this switch does not permanently mark the file for READ_CHECK; it merely selects a run-time option. To permanently mark the file for READ_CHECK, use the SET FILE/DATA_CHECK=READ command.
This attribute corresponds to the RCK option in the FAB$L_FOP field.
This attribute corresponds to the XAB$W_RVN field.
For DECnet for OpenVMS operations, this attribute enables file transfer mode, which is a data access protocol (DAP) feature that allows several records to be transferred in a single network operation. It maximizes throughput for single-direction, sequential-access file transfer.
This attribute corresponds to the SQO option in the FAB$L_FOP field.
If you also set DELETE_ON_CLOSE to YES, the file is deleted after the batch job completes.
This attribute corresponds to the SCF option in the FAB$L_FOP field and is not supported for DECnet for OpenVMS operations.
If you successfully create a new file with the same name, type, and version as an existing file, the old file is deleted.
SUPERSEDE is overridden by the CREATE_IF attribute.
This attribute corresponds to the SCF option in the FAB$L_FOP field.
You cannot create a file that has this attribute by using the CREATE/FDL command or the FDL$CREATE routine, because these commands open and then close the data file before it can be used. You can only use the FDL$PARSE routine to create a file that has the TEMPORARY attribute.
This attribute corresponds to the TMD option in the FAB$L_FOP field.
This attribute corresponds to the TEF option in the FAB$L_FOP field.
This attribute corresponds to the UFO option in the FAB$L_FOP field and is not supported for DECnet for OpenVMS operations.
This attribute corresponds to the FAB$B_RTV field and is not supported for DECnet for OpenVMS operations.
This switch does not permanently mark the file for WRITE_CHECK; it sets an RMS run-time option. You must use the SET FILE/DATA_CHECK=WRITE command to mark the file permanently.
This attribute corresponds to the WCK option in the FAB$L_FOP field.
4.1.8 KEY Section
The KEY primary attribute acts as a header for a section of the FDL file that describes keys. You must specify a separate KEY section for each key of an indexed file. The number of the key being described follows the word KEY (for example, KEY 0, KEY 1,...KEY n). The KEY value for the primary key must be 0. The KEY value for secondary keys can be numbered from 1 to 254.
The KEY primary attribute corresponds to the XAB$B_REF field.
The following table lists the KEY secondary attributes and their default values. Note that all KEY secondary attributes are create-time attributes.
Secondary Attribute | Default Value |
---|---|
CHANGES | NO |
COLLATING_SEQUENCE | None (only present for files with collated keys) |
DATA_AREA | None |
DATA_FILL | Same as bucket size |
DATA_KEY_COMPRESSION | YES |
DATA_RECORD_COMPRESSION | YES |
DUPLICATES | NO for primary; YES for alternate |
INDEX_AREA | None |
INDEX_COMPRESSION | YES |
INDEX_FILL | Same as bucket size |
LENGTH | None |
LEVEL1_INDEX_AREA | None |
NAME | Null-string |
NULL_KEY | NO |
NULL_VALUE | ASCII null character |
POSITION | None |
PROLOG | System or process default |
SEGn_LENGTH | None |
SEGn_POSITION | None |
TYPE | STRING |
CHANGES
This switch allows an RMS Update operation to change the value of the key. Such a change is not allowed for the primary key (regardless of this attribute), so the default setting for primary keys is NO. With alternate keys the default setting is also NO, but you can specify YES to allow changes to alternate key values.This attribute corresponds to the CHG option in the XAB$B_FLG field.
COLLATING_SEQUENCE
The name of the NCS collating sequence that defines the sorting order of the characters for this key. The value is a string from 1 to 31 characters long. You must supply the value; there is no default.This attribute corresponds to the XAB$L_COLNAM field.
DATA_AREA
This numeric attribute identifies the area where you place the data records in an indexed file with multiple areas. The value is an integer in the range 0 to 254, which must be the same number as that assigned to the area in an AREA section.The DATA_AREA, LEVEL1_INDEX_AREA, and INDEX_AREA values are used when the data level and the index levels are placed in separate areas or when each key is placed in its own area.
This attribute corresponds to the XAB$B_DAN field.
DATA_FILL
This attribute establishes the percentage of bytes in each data bucket in the area you want populated initially. If you anticipate that many records will be inserted randomly into the file, this value should be less than 100 percent of the bytes. The default value is 100 percent, and the minimum value is 50 percent. The /FILL_BUCKETS qualifier to the CONVERT command overrides this attribute.This attribute corresponds to the XAB$W_DFL field except that XAB$W_DFL contains a byte count, not a percentage.
DATA_KEY_COMPRESSION
This switch compresses leading and trailing repeating characters in the primary key and its default value is YES. For compression to occur, your indexed file must be defined as a Prolog 3 file with the FDL attribute KEY PROLOG. However, KEY PROLOG 3 is the default.This attribute corresponds to the KEY_NCMPR option in the XAB$B_FLG field, and should be set for DECnet for OpenVMS operations.
DATA_RECORD_COMPRESSION
This switch controls whether repeating characters are compressed in the data records. The default is YES; however, for compression to occur, your indexed file must be defined as a Prolog 3 file.
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