[uuid, helpfile("filename") [, optional-attribute-list]] library {library statements};
[uuid(. . .),helpfile("filename.hlp"),lcid(0x0409), version(2.0)]
library Hello
{ . . .};
The helpfile attribute sets the name of the Help file for a type library. All types in a library share the same Help file.
Use the GetDocumentation functions in the ITypeLib and ITypeInfo interfaces to retrieve the filename.
library, ODL File Syntax, ODL File Example, Generating a Type Library With MIDL