Using boolean values in C?

Question

C doesn't have any built-in boolean types. What's the best way to use them in C?

Answer 1

Nope, C doesn't, but C++ does.

In practice, any simple C program can be compiled using the C++ compiler ... but for complex applications, you might have far too many little issues to fix, since ANCI C compilers are more "forgiving" that most C++ compilers.

A much more suitable approach would be to define a bi-value enum called bool using typedef - see below:

typedef enum { false, true } bool;

This effectively provides a Developer Defined Type called "bool" that can be used exactly as we use bool in C++ ....

// g++ will compile this without error, but gcc will not.

#include

int main() {

bool flag = true;

if( flag ) puts("ok");

return 0;

}

// both g++ and gcc will compile this.

#include <stdio.h>

typedef enum { false, true } bool;

int main() {

bool flag = false;

if( flag ) puts("ok");

return 0;

}