DFS3578A OPEN ERROR FOR DDNAME = `ddname` RETURN CODE = 12

Explanation
 An attempt to open a BPAM data set failed. Return
code 12 is a Sort/Split utility return code, not a return code from
OPEN.

System action
 The utility function was terminated.

Programmer response
 See Data Administration: Macro Instruction
Reference for MVS/DFP (SC26-4506).