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假设以下 C 代码在 32 位平台上运行(因此 sizeof(int) = 4),以下代码是否可在大端和小端之间移植?当我问“它是否便携”时,我的意思是应用程序会打印:

a) 在小端平台上

Address is 0xAABBCCDD
MSB is AA
LSB is DD
little endian

b) 在大端平台上

Address is 0xAABBCCDD
MSB is AA
LSB is DD
big endian

?

#include <stdio.h>

typedef unsigned char uint8;
typedef unsigned int uint32;

#define is_bigendian() ( (*(uint8*)&var) == 0 )

int main()
{
    uint32 var = 1;
    uint8 msb;
    uint8 lsb;
    printf("Address is %x\n", (uint32)&var);
    msb = (((uint32)&var) & 0xFF000000) >> 24;
    lsb = (((uint32)&var) & 0x000000FF) >> 0;
    printf("MSB is %x\n", msb);
    printf("LSB is %x\n", lsb);
    if (is_bigendian())
    {
        printf("big endian\n");
    }
    else
    {
        printf("little endian\n");
    }
    return 0;
}
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