Fixing differences caused by language elements

In general, you can expect portable COBOL programs to behave the same way on the AIX workstation as they do on the mainframe. However, be aware of the differences in file-status values used in I/O processing.

If your program responds to file-status data items, be concerned with two issues, depending on whether the program is written to respond to the first or the second file-status data item:

related references  
FILE STATUS clause (COBOL for AIX Language Reference)
File status key (COBOL for AIX Language Reference)