unit testing for CTRL-C sent to an application

Question

I am developing an application handling CTRL-C. I am producing a signal handler to shut-down gracefully threads and other resources.

I want to

Answer 1

Introduce a level of indirection.

1. Place your high-level program code behind a Facade (I use a class named Program).
2. Have that Facade provide a shutdown() method, which performs all of the shutdown operation except calling std::exit().
3. Unit test that shutdown() method as you would any other method.
4. Have the signal handler delegate to that shutdown() method for the static Program object that represents your entire program then call std::exit(). This is the only part you can not unit test.