Messages

In addition to writing trace data in the form of ATB6xxxxI messages, the API trace facility also issues messages to report:

Successful and unsuccessful completion of an ATBTRACE START, STOP, or LIST request.
Syntax errors in a START, STOP, or LIST request.
Incorrect programming environment for ATBTRACE invokers.
Incorrect security authorization for START and STOP requests.
Allocation or other problems with the data set specified on START and STOP requests.
Timing or sequence problems (for example, delays in processing requests, START requests issued before STOP processing completes, and so on).
Suspension or termination of API tracing activity by APPC/MVS. These conditions might result in the loss of trace data.

The method you use to invoke an ATBTRACE request determines where APPC/MVS returns these status and error messages; see sections of Methods of Invoking the ATBTRACE REXX Exec for details.