CLIv2 provides the interface for mainframe applications to communication with one or more database systems. CLIv2 is a set of subroutines that are called by an application, so CLIv2 executes in the application's address space or virtual machine. Under MVS, applications running as IBM CICS or IBM IMS transactions are also supported by CLIv2.
Applications written in Assembler, PL/I, COBOL, C, C++, or other languages that have a CALL-type statement and use standard operating system linkage conventions (such as FORTRAN or PASCAL) call CLIv2 routines directly. After the program is compiled, a CLIv2 stub is included and a load module is created. When the application calls a CLIv2 routine, the CLIv2 stub dynamically loads the CLIv2 runtime, which sends the request to or receives a response from TDP.
CLIv2 is the current application programming interface. While an older version exists, it is deprecated for new application development. For complete information about CLIv2, see Teradata® Call-Level Interface Version 2 Reference for Mainframe-Attached Systems, B035-2417.