You communicate with EREP using keyword parameters and control statements.
Parameters tell EREP which report to run, which records to use for the report, and what to do with the records when the report is complete.
Control statements tell EREP what your hardware configuration is like, how many processors you have, whether or not your I/O devices are shared by more than one processor, and exactly where the devices are. Control statements also give EREP other information, such as limits on the number of errors included in any report.
All operating systems use the same parameters and controls to tell EREP what specific information to print in the reports.
If you run EREP using no controls at all, EREP produces detail summary reports (and data reduction reports, if your installation includes 3370 DASD) of all the records on the ERDS. The reports do not combine the records from shared I/O devices, nor do they identify the records as being from shared devices. EREP writes the records to a history file if one is available to receive them; if none is available, EREP issues an error message and the job or step abends.