I've seen that NetNamedPipeBinding exists in C# and in C++ (source) and I would like to know if it's possible to use it to transmit datas between a C++ program and a C# application?
If your C++ compiler is a recent version of Visual C++, with all the extensions to support writing managed code, then you can use WCF easily to pass data between a C++ program and a C# application.
If your C++ compiler doesn't support managed code extensions, you can still do it but it is a lot of work, because the WCF channel stack uses some layered proprietary protocols for message framing, security negotiation and message encoding, which you would need to reimplement on the C++ side if you can't use the managed implementation provided by WCF. See for example this question for the kind of issues which arise.
If you can't do managed C++ it is often much easier to forego some of the benefits provided by WCF and, depending on your requirements, either to: