When an error occurs in any IML module, IML pauses in the module and prints error diagnostics with a full traceback that can help in locating the problem. In the case of loaded modules, however, the traceback includes line offsets instead of the absolute SAS LOG line numbers. The offsets can be used to track the problem into the actual source code that originally defined the module. The START statement at the beginning of the module definition is always at offset=1.

Note that offsets apply only to loaded modules. For modules explicitly defined in any given session, absolute line numbers are printed in the traceback.