Why is void f(…) not allowed in C?

Question

Why doesn\'t C allow a function with variable length argument list such as:

void f(...)
{
    // do something...
}

Answer 1

With variable-length argument list you must declare the type of the first argument - that's the syntax of the language.

void f(int k, ...)
{
    /* do something */
}

will work just fine. You then have to use va_list, va_start, va_end, etc. inside the function to access individual arguments.