Return codes
High Level Assembler issues return codes that you can check with the IF and ON job control statements. The IF and ON job control statements let you skip or run a job step, depending on the results (indicated by the return code) of a previous job step. See z/VSE: System Control Statements for details about the IF and ON job control statements.
The return code issued by the assembler is the highest severity code that is associated with any error detected in the assembly, or with any MNOTE message produced by the source program or macro instructions. The return code can be controlled by the FLAG(n) assembler option described on page FLAG. See High Level Assembler messages for a listing of the assembler errors and their severity codes.