系统大小端测试程序

#include <stdio.h>

#ifndef  BOOL
typedef enum BOOL_type {FALSE=0, TRUE=1} BOOL;
#endif

#ifndef uchar
typedef  unsigned char  uchar;
#endif
#ifndef ushort
typedef  unsigned short int  ushort;
#endif

BOOL isSmallEndianSys(void);

void main(void)
{
printf("System Endian order test: %s Endian\n",
isSmallEndianSys() ? "Small" : "Big");
}

BOOL isSmallEndianSys(void)
{
union {
uchar  LowByte;
ushort Short;
} TestEndian;
TestEndian.Short = 0x0001;
return ((0x01 == TestEndian.LowByte) ? TRUE : FALSE);
}

#include <stdio.h>

void main(void)
{
const unsigned short int num = 0x0001;
printf("System Endian order test: %s Endian\n",
*((unsigned char *) &num) ? "Small" : "Big");
}