The /app_config switch selects application-configuration mode, which allows you to use some ACF keywords in the IDL file. With this MIDL compiler switch, you can omit the ACF and specify an interface in a single IDL file.
This switch has no parameters.
Microsoft RPC supports the use of the following ACF attributes in the IDL file:
Future releases of Microsoft RPC may support the use of other ACF attributes in the IDL file. The /app_config option represents a Microsoft extension to the OSF-DCE specification and, as such, is mutually exclusive with the /osf option.
midl /app_config filename.idl