typedef RPC_BINDING_HANDLE handle_t;
A binding handle is a pointer-sized opaque variable containing information that the RPC run-time library uses to access binding information. The run-time library uses binding information to establish a client-server relationship that allows the execution of remote procedure calls.
Based on the context in which a binding handle is created, the binding handle is considered a server binding handle or a client binding handle.
A server binding handle contains the information necessary for a client to establish a relationship with a specific server. Any number of RPC API run-time routines return a server binding handle that can be used for making a remote procedure call.
A client binding handle cannot be used to make a remote procedure call. The RPC run-time library creates and provides a client binding handle to a called server procedure (also called a server manager routine) as the RPC_BINDING_HANDLE parameter. The client binding handle contains information about the calling client.
The RpcBinding* and RpcNsBinding* routines return the status code RPC_S_WRONG_KIND_OF_BINDING when an application provides the incorrect binding-handle type.
An application can share a single binding handle across multiple threads of execution. The RPC run-time library manages concurrent remote procedure calls that use a single binding handle. However, the application is responsible for binding-handle concurrency control for operations that modify a binding handle. These operations include the following routines:
For example, if an application shares a binding handle across two threads of execution and resets the binding-handle endpoint in one of the threads by calling RpcBindingReset, the binding handle in the other thread is also reset. Similarly, freeing the binding handle in one thread by calling RpcBindingFree frees the binding handle in the other thread.
If you don't want concurrency, you can design an application to create a copy of a binding handle by calling RpcBindingCopy. In this case, an operation to the first binding handle has no effect on the second binding handle.
Note In 16-bit Windows applications, a task may only have a single RPC call outstanding at a time. Binding handles are allocated on a per-task basis and cannot be shared between tasks.
Routines requiring a binding handle as an argument show a data type of RPC_BINDING_HANDLE. Binding-handle arguments are passed by value.