Issue a command to the command line

In C++ we can use the system command to call anything we would from the command line.

For example, on osx:

void ofApp::keyPressed(int key){
    if (key == ' '){
        system("say 'hello world'");

Depending on your operating system there might be other things to consider. For example, on posix systems, you might want to use the & at the end of your command so that it runs in the background.

The systemSpeakExample in examples/input_output has good information about this and more details per-platform.