Beginning with Version 3 of IBM COBOL for AIX, STL and SdU (SMARTdata Utilities) files are not limited to a maximum size of 2 GB as they were in earlier versions of COBOL for AIX®.
By default, STL and SdU files created using OPEN OUTPUT statements have metadata (internal control information), referred to as large-format, that supports the increased file size. This feature is in general transparent to COBOL application programs. Note that only the maximum file size increased; the maximum sizes of individual records did not increase.
STL and SdU files created by COBOL for AIX programs before Version 3 have small-format metadata. You can open small-format files using OPEN INPUT, OPEN I-O, or OPEN EXTEND statements, but the files continue to be limited to the 2 GB maximum size.
For compatibility with COBOL for AIX Version 2, you can specify runtime option FILEMODE(SMALL) when you run a COBOL for AIX program to indicate that the program should create small-format STL and SdU files.
You can process large-format files with COBOL for AIX Version 2 programs if you run those programs using the current runtime library.
related tasks
Identifying files
related references
SdU file system
STL file system
File-system summary
Compiler limits (COBOL for AIX Language Reference)