Using SAS Automatic Variables

The following SAS automatic variables are created when a VSAM data set is accessed and set when records in the data set are accessed. (Records are accessed when an INPUT or a PUT statement that reads or writes a record executes.) The following automatic variables are not added to any SAS data sets created by a DATA step:
_RBA_
contains the RBA of the last record accessed.
Note: The _RBA_ variable is set to zero when a path is defined over an alternate index.
_IORC_
is set to the VSAM input/output return code.
_FDBK_
is set to the VSAM feedback code.
_RRN_
contains the RRN of the last RRDS record accessed. This variable is not created for ESDS and KSDS data sets.