Common errors in routines

These common errors have simple solutions:

If you receive abend U4093, reason X'224' (548 decimal), then make sure you use MEMLIMIT to allow access to above the 2 GB bar. For more information, see z/OS MVS Programming: Extended Addressability Guide.
If you do not have enough virtual storage, increase your region size or decrease your storage usage (stack size) by using the storage-related runtime options and callable services. (See Controlling storage allocation for information about using storage in routines.)
If you do not have enough disk space, increase your disk allocation.
If executable files are not available, check your executable library to ensure that they are defined. For example, check your STEPLIB or JOBLIB definitions.

If your error is not caused by any of the items listed above, examine your routine or routines for changes since the last successful run. If there have been changes, review these changes for errors that might be causing the problem. One way to isolate the problem is to branch around or comment out recent changes and rerun the routine. If the run is successful, the error can be narrowed to the scope of the changes.

Changes in optimization levels, addressing modes, and input/output file formats can also cause unanticipated problems in your routine.

In most cases, generated condition tokens or runtime messages point to the nature of the error. The runtime messages offer the most efficient corrective action. To help you analyze errors and determine the most useful method to fix the problem, Table 1 lists common error symptoms, possible causes, and programmer responses.

Table 1. Common error symptoms, possible causes, and programmer responses
Error Symptom	Possible Cause	Programmer Response
Numbered runtime message appears	Condition raised in routine	For any messages you receive, read the Programmer Response. For information about message structure, see Interpreting runtime messages below.
User abend code < 4000	A non-Language Environment abend occurred The assembler user exit requested an abend for an unhandled condition of severity ≥2	See the Language Environment abend codes in z/OS Language Environment Runtime Messages. Check for a subsystem-generated abend or a user-specified abend.
User abend code ≥ 4000	Language Environment detected an error and could not proceed An unhandled software-raised condition occurred The assembler user exit requested an abend for an unhandled condition of severity 4	For any abends you receive, read the appropriate explanation listed in the abend codes section of z/OS Language Environment Runtime Messages.
System abend with TRAP(OFF)	Cause depends on type of malfunction	Respond appropriately. See the messages and codes information of the operating system.
System abend with TRAP(ON)	System-detected error	See the messages and codes information of the operating system.
No response (wait/loop)	Application logic failure	Check routine logic.
Unexpected message (message received was not from most recent service)	Condition caused by something related to current service	Generate a traceback using `cdump()` or `ctrace()`.
Incorrect output	Incorrect file definitions, storage overlay, incorrect routine mask setting, references to uninitialized variables, data input errors, or application routine logic error	Correct the appropriate parameters.
No output	Incorrect ddname or file definitions	Correct the appropriate parameters.
Nonzero return code from enclave	The return code was issued by the application routine	Check the application for the meaning of the return code.