When you generate a COBOL program, the sysCodes build descriptor option determines the source of the return code that is placed in the sysVar.errorCode system variable in response to a file I/O error. The option is also available in the EGL Debugger.
For more information, including specific error values, see errorCode in the EGL Language Reference.
The codes are specific to the target runtime environment and to the type of resource being accessed (for example, VSAM instead of a transient data queue). For details on the meaning of specific error codes, see the documentation for the subsystem you are using (such as VSAM or CICS®).