Differences between the X/Open CPI-C interface

This section describes all the extensions and special features of CPI-C with the UPIC carrier system compared to the X/Open CPI-C interface.

Extensions compared to CPI-C

• The following additional UPIC-specific functions are offered. These are:

  Enable_UTM_UPIC
  Extract_Client_Context
  Extract_Conversation_Encryption_Level
  Extract_Cursor_Offset
  Extract_Convertion
  Extract_Max_Partner_Index
  Extract_Partner_LU_Name_Ex
  Extract_Secondary_Return_Code
  Extract_Shutdown_State
  Extract_Shutdown_Time
  Extract_Transaction_State
  Disable_UTM_UPIC
  Set_Allocate_Timer
  Set_Client_Context
  Set_Conversation_Encryption_Level
  Set_Conversation_New_Password
  Set_Convertion
  Set_Function_Key
  Set_Partner_Host_Name
  Set_Partner_Index
  Set_Partner_IP_Address
  Set_Partner_Port
  Set_Partner_Tsel
  Set_Partner_Tsel_Format
  Set_Receive_Timer
  Specify_Local_Port
  Specify_Local_Tsel
  Specify_Local_Tsel_Format
  Specify_Secondary_Return_Code

  The Enable_UTM_UPIC and Disable_UTM_UPIC functions regulate the signing on and signing off of CPI-C programs with the UPIC carrier system. If these two calls are not used, it is not possible to connect to a UTM application. For further details, see section “CPI-C calls in UPIC” and chapter “Configuration”.

• With UPIC the Send_Mapped_Data and Receive_Mapped_Data calls are used to send and receive format names.

• Automatic conversion of user data by configuration

  This also allows for the possibility of automatic code conversion of user data between ASCII and EBCDIC code; see also section “Code conversion”. On the one hand, this reduces the effort involved in creating an application, while on the other hand it enables a single CPI-C program to communicate both with a UTM application on a Unix or Linux system based on ASCII code and with a UTM application on a BS2000 system based on EBCDIC code (if the user data does not contain any binary information that would be corrupted in the code conversion process).

Special features of CPI-C implementation

• The name for partner_LU_name can be up to 73 characters long; for a local connection via UPIC local (Unix, Linux and Windows system) it can only be up to 8 characters.

• The name for TP_name can be up to 8 characters long.

The prototypes, parameter types, and constants are described in detail in the header file upic.h.