The STL file system (standard language file system) supports sequential, indexed, and relative files. It provides the basic file facilities for accessing files.
The STL file system conforms to 85 COBOL Standard, and provides good performance and the ability to port easily between AIX® and Windows-based systems.
The STL file system is safe for use with threads. However, you must ensure that multiple threads do not access the level-01 records for the file at the same time. Multiple threads can perform operations on the same STL file, but you must use a pthread_cond_wait call or its equivalent to force all but one of the threads to wait for the file access to complete on the active thread.
related concepts
File organization and access mode
related references
File-system summary
STL and SdU files that are larger than 2 GB