Using the COBOL debug file user exit interface

The name of the COBOL debug file user exit is:

IGZIUXB for non-CICS
IGZIUXC for CICS®

The COBOL debug file user exit is loaded the first time you need to use a COBOL debug file. If the load of the user exit is not successful, Language Environment does not issue a message and does not attempt to call the user exit.

Syntax

For IGZIUXB (non-CICS):

IGZIUXB(Interface_Version,                                                    
          Name_Of_Debug_File,                                                   
          Name_Of_CU)

For IGZIUXC (CICS):

IGZIUXB(Interface_Version,                                                    
          Name_Of_Debug_File,                                                   
          Name_Of_CU,                                                           
          CICS_SYSTEM_EIB)

Where:

Interface_Version (INPUT): Is a 4-byte integer with interface version. The value is 1.
Name_Of_Debug_File (INPUT/OUTPUT): Is a halfword-prefixed 256-byte character string that has the name of the debug file. This is an input/output field. On input it contains the name of debug file name that was used at compile time. On output, the name length and name can be updated by the user exit. The new name information is used by the runtime when R15 is zero on return. The name is not padded with blanks on input. On output, the name length must reflect the length of the name without blanks.
Name_Of_CU (INPUT): Is a halfword-prefixed 160-byte character string that has the name of the compile unit. The compile unit name of a program is the program name. The compile unit name of a class is the class name.
CICS_SYSTEM_EIB (INPUT): Is the CICS system EIB (EXEC Interface Block)

CICS considerations

CICS commands can be used in the COBOL debug file user exit. However, the COBOL debug file user exit must adhere to the following conventions when using EXEC CICS commands: The COBOL debug file user exit must use the CICS system EIB with the SYSEIB translator option. The CICS commands must use the RESP option.

Register conventions

Table 1. Register conventions for the COBOL debug file user exit
Register	Description
1	Address of the parameter list
12	Address of the CAA
13	Address of a dynamic save area (DSA). The user exit routine can save the registers here across its processing
14	Contains the return address
15	Contains the entry point address upon entry and the return code upon exit

Usage notes

The COBOL debug file user exit must be written in assembler language and must be reentrant. If you write the COBOL debug file user exit in Language Environment-enabled assembler, you must specify MAIN=NO on the CEEENTRY macro.
The COBOL debug file user exit must not call any HLL programs. However, it can call other assembler routines.
The COBOL debug file user exit must not create a Language Environment enclave.
R15 must be set to zero upon return when the debug file name is changed. If R15 is nonzero, any change to the debug file name is ignored.
Changes to the file name must be fully qualified. If the debug file is a PDS or a PDSE, the file name returned from the user exit must be the name of the PDS/PDSE along with the member name.
The COBOL debug file user exit is called in AMODE(31) and must return in AMODE(31).