Problem analysis is supported by background job logs that record all messages issued by programs run in the background. The only exception to this is that batch-input messages are recorded in the batch input log available from Transaction SM35 instead of in the background processing log. Whether or not external program output is logged depends on whether the external program is started synchronously or asynchronously, as well as how the job-step program-output control flags are set. In the case of an asynchronous background job, the background processing system does not wait for an external command or program to complete before starting the next job step or completing the job. Output from this program would not be captured in the job log.