Stringizing operator

Question

How does the following code compile correctly,

#include <stdio.h>
#define stringer( x ) printf_s( #x "\n" )
int main() {
stringer( "In quotes when printed to the screen" );   
}

isn't it supposed to get expanded into

printf_s(""In quotes when printed to the screen""\n");

which is an error as there are nested double quotes in printf_s??

Answer 1

No, the # operator handles character string literals specially. It must \ escape each " in a character string literal that is passed to it. The correct expansion is:

printf_s( "\"In quotes when printed to the screen\"" "\n" );

Answer 2

No, it's expanded into

printf_s("\"In quotes when printed to the screen\"" "\n");

which will finally be

printf_s("\"In quotes when printed to the screen\"\n");

and should print

"In quotes when printed to the screen"