BOOL 是char
bool b1 當b1>0 就＝YES
BOOL b2 當b2=1 才＝YES
所以框架都用BOOL
Boolean mac os上有歷史意義的類型
Boolean types and values
Boolean Mac OS historic type, sizeof(Boolean)==1
bool Defined in stdbool.h, ISO C/C++ standard type
false Now defined in stdbool.h
true Now defined in stdbool.h
boolean_t i386
/*
* File: boolean.h
*
* Boolean type, for I386.
*/
#ifndef _MACH_I386_BOOLEAN_H_
#define _MACH_I386_BOOLEAN_H_
#if defined(__x86_64__) && !defined(KERNEL)
typedef unsigned int boolean_t;
#else
typedef int boolean_t;
#endif
#endif /* _MACH_I386_BOOLEAN_H_ */