I’m not quite clear what your problem is; it sounds like there might several.
Are you saying that your code is in C, but that C++ rules are incorrectly being run against it? SLVS should be apply the appropriate rules based on the file extension. Or are the C++ rules reporting issues against the header files?
If you are using connected mode then SonarLint will be using a specific ruleset already. However, if you have file exclusions defined on the server they aren’t currently taken in to account by SonarLint (we have a ticket in the backlog for this). Could that account for the difference?
In addition to what @duncanp mentioned, If you see Cpp rules triggering on C header. Make sure your project setting is set to C explicitly. We detect the language based on that option since C and C++ headers have the same extension.
Thank you, what I meant is that I see issues from cpp dictionary in my header files. i l take into account your suggestion about exclusion, but at the moment I don’t have them.