The XPI copy books
For each XPI function, a copy book provides the DSECTs associated with that function. These DSECTs allow you to map the parameters and the response and reason codes of an XPI call.
You must include in your exit program a COPY statement for each XPI function that you are going to use. The copy book name is the same as the macro name, except that the final letter “X” becomes a letter “Y”.
For example, to include the copy book for the XPI function DFHSMMCX,
you must include the statement:
COPY DFHSMMCYTrace entries for your XPI calls show these parameter lists if you have tracing on for the function you are using.