查看本机大小端little_endian & big_endian

include "stdio.h"

int main(){
int a = 0x01;
char *c = (char *)a;
if(c[0] = 1)
printf("little endian");
else
printf("big endian");
return 0;
};

第二种：
使用union，union 只会为一个变量提供空间。

include "stdio.h"

union {
int a;
char b;
}u;
int main(){
u.a = 1;
if(u.b == 1){
printf("little endian");
else
printf("big endian");
return 0;
}