C variadic functions (a)

Follows from C variadic functions.

Passing variadic arguments from one variadic function to the other is not possible. Instead we have to implement a function variant taking va_list instead. These variants usually start with v in standard library. See vprintf and variations.

This is how we can implement v variation of functions along with keeping the variadic function too.

void foo(const char* format, ...) {
	va_list args;
	va_start(args);
	// Do something before & after calling vbar
	vbar(format, args);
	va_end(args);
}
 
void bar(const char* format, ...) {
	va_list args;
	va_start(args);
	vbar(format, args);
	va_end(args);
}
 
void vbar(const char* format, va_list list) {
	// va_start and va_end are taken care of outside
	// Just do stuff with args here
}