The
Interface Proxy File
The interface
proxy file (name_P.C) is a C file that contains routines equivalent to
those in the client stub, server stub, and client and server files of an RPC
interface. This file contains implementations of CProxyInterface and CStubInterface
classes that are derived from the CProxy and CStub classes of the
base interface. For example, an interface named ISomeInterface derived from the
IUnknown interface is implemented in the CProxyISomeInterface and
CStubISomeInterface classes derived from the CProxyIUnknown and CStubIUnknown
classes.
The interface
proxy file includes the following sections:
The implementation of a CProxyInterface
class.
The virtual member functions of this class provide a client
application s surrogate entry points for each of the interface functions. These
member functions marshal the input arguments into a transmittable form,
transmit the marshalled arguments along with information that identifies the
interface and the operation, and then unmarshal the return value and any output
arguments when the transmitted operation returns.
The implementation of a CStubInterface
class.
The virtual member functions of this class provide an object server s
surrogate entry points for each of the interface functions. These member
functions unmarshal the input arguments, invoke the server s implementation of
the interface function, and then marshal and transmit the return value and any
output arguments. A CStubInterface class also includes a member function
that is invoked by the RPC run-time library when a client application calls one
of the interface functions. This routine calls the surrogate routine specified
by the RPC message.
Marshalling and unmarshalling
support routines for complex data types.
Use the /proxy MIDL compiler switch to
override the default name of the interface proxy file. The /env and /out switches affect this file.