C99 boolean 数据类型？

Question

什么是 C99 boolean 数据类型以及如何使用它？

Answer 1

包括 <stdbool.h> 标题

#include <stdbool.h>

int main(void){
  bool b = false;
}

宏 true和 false扩展到 1和 0分别。

第7.16 boolean 类型和值 < stdbool.h >

• 1 The header <stdbool.h> defines four macros.
• 2 The macro
  • bool expands to _Bool.
• 3 The remaining three macros are suitable for use in #if preprocessing directives. They are
  • true : which expands to the integer constant 1,
  • false: which expands to the integer constant 0, and
  • __bool_true_false_are_defined which expands to the integer constant 1.
• 4 Notwithstanding the provisions of 7.1.3, a program may undefine and perhaps then redefine the macros bool, true, and false.