What does the colon signify in a C function?

Question

What is this use of the colon called?

The following code is taken from the book Learn Core Audio.

    int main(int argc, const char * argv[])
           


        

Answer 1

Cleanup is a label. You can use

goto cleanup;

In your code to redirect your execution from cleanup label.

Answer 2

cleanup: is a label. It can be used as the target for a goto statement.

Answer 3

That's a label. It's used along with a goto statement to control the flow of your program.

goto and Labeled Statements (C)