is there a way to have midl generate each interface in a separate .h ?

I have a bunch of objects that inherit abstracts interfaces generated from an idl file. Each object that use of theses interfaces include the same file interfaces.h which contain all the c++ generated abstract classes that map to the idl interface.

Each time I change anything into interfaces.idl every classes that depend on this have to be rebuild since interfaces.h change. Is there a flag or something to tell midl to generate each abstract class in its own .h ?

From stackoverflow

• The only way I can think of is to put each interface in its own IDL file, or divide them into multiple IDLs according to rate-of-change.

  Then include (or is it #import -- I forget) these interface IDLs into the main library IDL, which will produce the type library, if you need that.

  Emmanuel Caradec : That's possible but not very easy to do because I integrate typelib inside the application. Adding a separate library for each would be painful. Midl has everything it needs to split the .h, I expected someone give me the magic flag of the magic tool to do it.

  Kim Gräsman : There should still only need to be one type library -- have one master IDL that includes each interface IDL and contains the library block. Does that not work for you?

  Emmanuel Caradec : I should have read more carefully, this is exactly what I needed. Thanks.

• Here is a sample on how to organize the idl to generate separate .h files and a single typelib. The correct directive is import.

  main.idl

  import "oaidl.idl";
  import "ocidl.idl";
  
  import "frag1.idl";
  import "frag2.idl";
  
  [
      uuid(1BECE2AF-2792-49b9-B133-BBC89C850D6F),
      version(1.0),
      helpstring("Bibliothèque de types")
  ]
  library Library
  {
      importlib("stdole2.tlb");
  
      interface IFrag1;
      interface IFrag2;
  }
  

  frag1.idl

  import "oaidl.idl";
  import "ocidl.idl";
  
  [
      object,
      uuid(9AEB517B-48B9-4628-8DD3-4A0BA8D39BEF),
      dual,
      nonextensible,
      helpstring("Interface IFrag1"),
      pointer_default(unique)
  ]
  interface IFrag1 : IDispatch {
      HRESULT frag1();
  };
  

  frag2.idl

  import "oaidl.idl";
  import "ocidl.idl";
  
  [
      object,
      uuid(D60835D4-E1B1-40fb-B583-A75373EF15BE),
      dual,
      nonextensible,
      helpstring("Interface IFrag2"),
      pointer_default(unique)
  ]
  interface IFrag2 : IDispatch {
      HRESULT frag2();
  };