A custom FrontPage component implementation file is either a dynamic link library, a shared library, a stand-alone program, or a script. It can contain software implementing one or more components.
A custom component implementation is analogous to a CGI script. The component procedure is given three sets of name-value pairs:
Based on this information, the component must return some HTML representing a page fragment or an entire page.
A component can be implemented with a single procedure. When using the Standard I/O interface, this procedure is called implicitly by invoking the executable. A Standard I/O component implementation reads the dictionaries from its standard input and writes HTML to its standard output.
When using the DLL or shared library interface, you must export a single entry point named Shortname_Expand, where Shortname is the shortname of the component, exactly as specified (including case) in the component description file.