ctrlx SDK Realtime C

[DavidePalombo]

Hello everybody,

Our customer is planning to migrate their real-time code from an industrial PC to the ctrlX platform. The code is written in C and consists of a series of services managed by a task manager.

In the Real-Time SDK, I only find examples related to C++. Is it possible to use C, particularly to interface with the ctrlX scheduler?

Thank you in advance!

[Sgilk]

Hi @DavidePalombo ,

The realtime system of ctrlX OS utilizes the Apache Celix framework. You can absolutely run services written in C, but there will be some C++ required to build as a Celix bundle. There is an example in the realtime SDK (samples-cpp/plc-c-interface) which creates a Celix bundle containing services written in both C and C++.

To access the realtime SDK, a training is generally required. See this article.

[DavidePalombo]

Hi Sgilk, 

thank you for your reply. I'll be a bit more specific:

I already have access to the realtime SDK. I read the documentation so I know the realtime system of the ctrlX utilizes Apache Celix. In particular the Celix framework support building bundles written in C (e.g. celix/examples/celix-examples/hello_world_c at master · apache/celix).

My first idea was to build a Celix bundle directly written in C, but looking at the examples provided in the rt-SDK, they use external C++ files, in particular:

• "common/scheduler/i_scheduler3.h" for register the callable in the scheduler

• "comm/datalayer/datalayer.h" for interacting with the datalayer-rt
  
  

While with the non-realtime SDK there are C interfaces for accessing the datalayer, in this case I was not able to find any C interfaces related to these two header files.
It means that, if a build a C Celix bundle, it will not be able to interact with the scheduler and the datalayer-rt.
Is it correct, or am I missing something?

I understand that I could put my C code wrapped inside the C++ bundles, but that would mean a heavy refactoring of the code, since it is composed by tens of services and millions of lines of code.

Thanks!

[Sgilk]

@DavidePalombo ,

I don't believe we support C Celix bundles at this time. @nickH , please correct me if I'm wrong here.

Why would there need to be a heavy refactoring of the C services to wrap them in C++ bundles? I would think you could use them as is.