MIDL Binding Handles
Binding handles are data objects that represent the binding between the client and the server.
MIDL supports the base type handle_t. Handles of this type are known as "primitive handles."
You can define your own handle types using the [handle] attribute. Handles defined in this way are known as "user-defined" or "customized" or "generic" handles.
You can also define a handle that maintains state information using the [context_handle] attribute. Handles defined in this way are known as "context" handles.
If no state information is needed and you do not choose to call the RPC run-time libraries to manage the handle, you can request that the run-time libraries provide automatic binding. This is done by using the ACF keyword [auto_handle].
You can specify a global variable as the binding handle by using the ACF keyword [implicit_handle]. The [explicit_handle] keyword is used to state that each remote function has an explicitly specified handle.
For more information, see Binding and Handles.