If you have JOB INPUT filename, and filename is VSAM, don't bother checking the FILE-STATUS. Easytrieve is doing all that for you automatically. Unless, of course, you POINT to particular parts of the file, so do the check on the status after POINT. Or WRITE.
Don't know about the other types, not used them. I guess the manual would say, but I'm not going to look it up.
If you have JOB INPUT filename, and filename is "flat", again, nothing to check.
If you are doing controlled reads (GET) of a "flat" file, you use EOF to determin end-of-file, not FILE-STATUS. PUT will not return to your program if it has failed to write a record.