JCL allows you to identify one empty file, but you need to make sure that it is an input for IDCAMS. IDCAMS (Integrated Data Cluster ACCESS Method Services) is a utility used for creating, MODIFYING and deleting VSAM (Virtual Storage Access Method) datasets. When the file is input into IDCAMS, an error is thrown (return code 4 i.e., RC=4) if it's empty. 

Getting your feet wet with the JCL Interview Questions is necessary if you are looking for a job related to JCL. In preparation for your interview, our team has compiled a list of relevant JCL interview questions and answers. These JCL Interview Questions are intended to help you become acquainted with the type of questions that might be asked during an interview. This will COME in handy for FUTURE projects and INTERVIEWS. 

As an additional piece of advice, review past assignments you have done on the topic so that you are confident in your ability to speak about them. The interviewer expects you to answer basic questions if you are fresher, so you'll need to strengthen your basic concepts. Try to stay confident throughout the interview.