KSAM files are accessed from COBOL programs through calls to a set of procedures. These
procedures allow you to open, open for shared access, write records to, read records from, lock, unlock,
update, position, and close a KSAM file. (Refer to Table 3-1 “KSAM Procedures for COBOL Interface” for a list of the procedures and their
associated functions.) The COBOL procedures provided with KSAM/3000 correspond to the
INDEXED I-O module statements in COBOL 74.
Note: The following applies when using KSAM with COBOL.
The KSAM file must be created with KSAMUTIL's >BUILD command.
To access a KSAM file in chronological order, the KSAM file must be copied to a non-KSAM file.
KSAM permits duplicate primary keys as an extension to the ANSII standards.
In HP COBOL/3000, the procedures that are used to access KSAM files differ in form from the
COBOL input/output statements used to access non-KSAM files. The KSAM interface procedures
use parameters for information that would otherwise be specified in the FILE-CONTROL
paragraph and the FD entry of the DATA DIVISION. These parameters are themselves defined in the
WORKING-STORAGE section of the DATA DIVISION. The main restriction on the KSAM
interface call parameters is that they must start on word boundaries.
Table 3-1 KSAM Procedures for COBOL Interface
PROCEDURE NAME | PARAMETERS | FUNCTION | PAGE |
|---|
| CKCLOSE | filetable status | Terminates processing of KSAM file identified by
filetable. | 3-12 |
| CKDELETE | filetable status | Logically removes record from KSAM file; deleted
record is identified by previous read. | 3-13 |
| CKERROR | status, result | Converts numeric value returned in status to
character string result. | 3-17 |
| CKLOCK | filetable status lockcond | Dynamically locks file opened for shared access,
conditionally depending on lockcond. | 3-18 |
| CKOPEN | filetable status | Initiates processing of file named in filetable;
returns file number to first word of filetable. | 3-20 |
| CKOPENSHR | filetable status | Initiates processing with dynamic locking and shared
access of file named in filetable. | 3-25 |
| CKREAD | filetable status record recordsize | Reads next sequential record from KSAM file
identified by filetable into record. | 3-26 |
| CKREADBYKEY | filetable status record key keyloc recordsize | Reads into record first record with a key in location
keyloc whose value matches that of key, from KSAM
file identified by filetable. | 3-29 |
| CKREWRITE | filetable status record recordsize | Replaces last sequential record read by CKREAD,
or replaces record whose primary key matches the
value of key item in record, with the contents of
record. | 3-32 |
| CKSTART | filetable status relop key keyloc keylength | Positions record pointer in preparation for a
sequential read to the first record with a key in location
keyloc whose value has the relation relop to the
value of key. | 3-36 |
| CKUNLOCK | filetable status | Unlocks file dynamically locked by CKLOCK. | 3-40 |
| CKWRITE | filetable status record recordsize | Writes record of length recordsize from record to a
KSAM file identified by filetable. | 3-42
|
