Communications Blocks and Error Detection › Communications Blocks

Communications Blocks

Communications blocks return status information about requested database (CA IDMS/DB) and data communications (CA IDMS/DC and CA IDMS UCF) services to the application program. Depending on the usage mode (LR, DML, or MIXED) defined in the subschema, your program uses one or two of the following blocks:

• IDMS DB communications block—The IDMS DB communications block is used when your program specifies the BATCH operating mode.
• Logical-record request control (LRC) block—The LRC block is used when the subschema usage mode is either LR or MIXED. The DML precompiler copies the LRC block with either the IDMS DB communications block (operating mode of BATCH) or the IDMS DC communications block (operating mode of IDMS_DC or DC_BATCH).
• IDMS DC communications block—The IDMS DC communications block is used when your program specifies either IDMS_DC or DC_BATCH operating mode.

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DECLARE SUBSCHEMA