# 标准库stdbool.h

这个库可太简单了，一个函数都没有，只有几个宏。

```c
#ifndef _STDBOOL
#define _STDBOOL

#define __bool_true_false_are_defined	1

#ifndef __cplusplus

#define bool	_Bool
#define false	0
#define true	1

#endif /* __cplusplus */

#endif /* _STDBOOL */
```

去掉一些没用的只用三个有用的宏。第一个是bool，这个宏一般在C中用的并不多；第二个和第三个是false和true，这个分别定义为1和0。如果不包含这个库，其实也可以自己手写这两个宏。当然自己心里清楚就直接include了。
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