Running plugins in a sandbox

Question

I am designing a system in C/C++ which is extendible with all sort of plugins. There is a well defined C public API which mostly works with (const) char* and other

Answer 1

Simply put, you can't do that in the same process. If your plugins are written in C or C++, they can contain numerous sources of undefined behavior, meaning sources for undetectable unavoidable crashes. So you should either launch the plugins in their own processes like kassak suggested and let them crash if they want to, or use another language for your plugins, e.g. some intepreted scripting language like lua.