It is common practice to place lists of function prototype declarations in header files*.
Note that pre-ANSI C code does not use complete function prototype declarations. Rather, a function is declared by stating the type of its return value and following the function identifier with empty parentheses to distinguish it as a function rather than a variable:
float square();
The default return type for functions is int, and many pre-ANSI programs took advantage of this by not declaring those functions which returned ints at all.
While most ANSI C compilers permit these short cuts, it is considered good practice to provide full prototype declarations for all functions. In addition to aiding program
