High Level API

High level API uses the real-time environment TCT and the real-time environment’s Media Database components.

As a result

high level API cannot be used when the Control‑M/Tape real-time environment is not active
calling programs intended for use with high level API have to be APF-authorized

Control‑M/Tape high level API is implemented by the following Assembler macros:

Table 249 Assembler Macros for Implementing Control-M/Tape High Level APIs

Macro	Description
CTTACCDB	Accesses the Media Database.
CTTCHKDB	Checks the last access of the Media Database (using the CTTACCDB macro).

The following functions can be performed by high level API using macro CTTACCDB:

Table 250 High Level API Functions using the CTTACCDB macro

Function	Description
START	Initializes the high level API. Access of the Media Database must begin with this function.
READVOL	Reads a requested volume record from the Media Database.
ADDVOL	Adds a volume record to the Media Database.
DELVOL	Deletes a volume record from the Media Database.
UPDTVOL	Updates a volume record in the Media Database.
END	Terminates high level API functions. Access of the Media Database must end with this function.

After each run of the CTTACCDB macro, it is highly recommended that you check the completion code of the access to the Media Database using the CTTCHKDB macro. This macro tests the return code from the API and transfers control to an error handling routine that is written by the user as part of the calling program.

Parent Topic

Legacy APIs