The IDL Interface Body

The IDL interface body contains data types used in remote procedure calls and the function prototypes for the remote procedures. The interface body can also contain imports, pragmas, constant declarations, and type declarations. In Microsoft-extensions mode, the MIDL compiler also allows implicit declarations in the form of variable definitions.

The following example shows an IDL file containing the definition of an interface. The body of the interface definition, which occurs between the curly brackets, contains the definition of a constant (BUFSIZE), a type (PCONTEXT_HANDLE_TYPE), and some remote procedures (RemoteOpen, RemoteRead, RemoteClose, and Shutdown).

  uuid (ba209999-0c6c-11d2-97cf-00c04f8eea45), 
interface cxhndl 
  const short BUFSIZE = 1024;  
  typedef [context_handle] void *PCONTEXT_HANDLE_TYPE; 
  short RemoteOpen( 
      [out] PCONTEXT_HANDLE_TYPE *pphContext, 
      [in, string] unsigned char *pszFile 
   short RemoteRead( 
      [in]  PCONTEXT_HANDLE_TYPE phContext, 
      [out] unsigned char achBuf[BUFSIZE], 
      [out] short *pcbBuf 
  short RemoteClose( [in, out] PCONTEXT_HANDLE_TYPE *pphContext ); 
  void Shutdown(void); 

For more information see the MIDL Language Reference.