End to end testing framework for C++ application

I am testing a C/C++ application. For the majority of methods I was able to write unit tests using CppUTest. But there are a few for which not, and I want to write integration/end to end tests to test these methods too. What I want to test whether

• correct output file is generated

• for invalud arguments proper error messages are printed (it is a command line tool)

• it displays correct output messgaes

My question is whether there are tools for this, or should I write some scripts to invoke my application, capture output etc.? If yes, how to start these scripts? Invoke them from CppUtest?