A Runtime Callable Wrapper (RCW) is a

proxy Proxy may refer to: * Proxy or agent (law), a substitute authorized to act for another entity or a document which authorizes the agent so to act * Proxy (climate), a measured variable used to infer the value of a variable of interest in climate re ...

object generated by the .NET

Common Language Runtime The Common Language Runtime (CLR), the virtual machine component of Microsoft .NET Framework, manages the execution of .NET programs. Just-in-time compilation converts the managed code (compiled intermediate language code) into machine instructio ...

(CLR) in order to allow a Component Object Model (COM) object to be accessed from managed code. Although the RCW appears to be an ordinary object to .NET clients, its primary function is to

marshal Marshal is a term used in several official titles in various branches of society. As marshals became trusted members of the courts of Medieval Europe, the title grew in reputation. During the last few centuries, it has been used for elevated o ...

calls and data between a .NET client and a COM object. For example, a managed application written in C# might make use of an existing COM library written in C++ or Visual Basic 6, via RCWs. The runtime creates exactly one RCW for each COM object, regardless of the number of references that exist on that object. The runtime maintains a single RCW per process for each object. If you create an RCW in one application domain or apartment, and then pass a reference to another application domain or apartment, a proxy to the first object will be used.

External links

MSDN Runtime Callable Wrapper Reference
Component-based software engineering Inter-process communication Microsoft application programming interfaces Object-oriented programming Object models {{compu-prog-stub