大小端测试程序

方法一：

#include<stdio.h>
#include<stdlib.h>

int main(int argc ,char *argv[])
{
    union name{
        int i;
        char a;
    }c;
    c.i=0x04030201;

    printf("%d\n",c.a);//输出4为大端存储，输出1为小端存储
    return 0;
}

方法二：

#include  <stdio.h>

typedef union{
        unsigned int a;
        unsigned char b[4];
}Endian;

int main()
{
        Endian test;
        test.a=0x12345678;
        printf("%s\n",(0x12 == test.b[0])?"Big Endian":"Small Endian");

        return 0;
}

方法三：

#include<stdio.h>
#include<iostream.h>

void main()
{
    union w {
        int m ;
        char n ;
    };
    w  ww ;
    ww.m=1 ;
    if(ww.n==1)
        printf("it is little-endian ");

    else
        printf("it is libig-endian ");
}