判断主机的字节序

#include<stdio.h>

union
{
short s;
char c[sizeof(short)];
}test;

int main()
{
//method 1
int a = 0x12345678;
if(*((char *)&a) == 0x12)
printf("big-endian\n");
else
printf("little-endian\n");

//method 2
test.s = 0x0102;
if(sizeof(short) == 2)
{
if(test.c[0] == 1 && test.c[1] == 2)
printf("big-endian\n");
else
printf("little-endian\n");
}
return 0;

}

运行结果：

little-endian

little-endian