C语言实现大小端、编译系统bit位判断

1、简单判断机器大小端的C函数：

#include<stdio.h>

int main()
{
    int value = 0x0001;

    char *pointer = (char *)&value;

    if (*pointer == 1)
    {
        printf("Machine is Little Endian\n");
    }
    else if (*pointer == 0)
    {
        printf("Machine is Big Endian\n");
    }

    system("pause");
    return 0;
}

2、判断编译系统bit位方法

printf("system is %d Byte\n", sizeof(void *));