What is the printf format specifier for bool?

Question

Since ANSI C99 there is _Bool or bool via stdbool.h. But is there also a printf format specifier for bool?

I mean

Answer 1

If you like C++ better than C, you can try this:

#include <ios>
#include <iostream>

bool b = IsSomethingTrue();
std::cout << std::boolalpha << b;

Answer 2

To just print 1 or 0 based on the boolean value I just used:

printf("%d\n", !!(42));

Especially useful with Flags:

#define MY_FLAG (1 << 4)
int flags = MY_FLAG;
printf("%d\n", !!(flags & MY_FLAG));