The Callable File Handler, ExtFH, is a loadable file handling subsystem with an open architecture developed by Micro Focus. It can be used independently with a variety of programming languages, enabling you to create powerful file processing tools, as well as sophisticated database applications.

The Callable File Handler (ExtFH) enables programs to perform complex file operations that are not usually directly supported by your language syntax.

The main advantages provided by ExtFH are:

The ExtFH interface provides a way for applications to transparently access a file system such as DB2 and Oracle for record storage. In transaction processing environments, ExtFH is typically used to handle data access for batch programs.

You can also write your own file handler and run it in place of ExtFH, as long as it conforms to the interface defined by Micro Focus.