Managing Use of the APPC/MVS API Trace Facility

Using the application programming interface (API) trace facility, your installation can collect data about APPC/MVS and CPI-C calls that an APPC/MVS TP issues. With this data, your installation can diagnose not only errors that occur during a specific call, but also problems with the conversation flow between the TP and its partners. This diagnostic capability is useful in both testing and production environments.

z/OS MVS Programming: Writing Transaction Programs for APPC/MVS contains the following information about using the API trace facility:

Planning topics, such as possible security requirements for trace data sets; trace data set characteristics; and how to avoid losing trace data through wrapping or resource contention.
How to select values for the ATBTRACE START request, to ensure that APPC/MVS collects the trace data required to either verify in TP processing, or diagnose errors.
How to invoke the ATBTRACE REXX exec, including programming considerations, output, invocation methods, syntax diagrams, and parameter descriptions for each type of ATBTRACE request.
General descriptions and examples of trace data set entries, with suggestions for sorting and reading the entries.

Because you might have to start, stop, or list tracing activity yourself, you should be familiar with all the information about the API trace facility in z/OS MVS Programming: Writing Transaction Programs for APPC/MVS.