2.57-编写程序show_short, show_long和show_double,它们分别打印类型为short, long和double的C语言对象的字节表示。请试着在几种机器上运行。

#include <stdio.h>

//A byte pointer refers to a sequence of bytes
typedef unsigned char * byte_pointer;

//The input is a byte pointer and a byte number
void show_bytes(byte_pointer start, size_t len) {
    
	size_t i;
	for (i = 0; i < len; i++) {
    
		//A storage unit holds one byte
		printf("%.2x ", start[i]);
		//Output in hexadecimal format with at least two digits
	}
	printf("\n");
}


//show_short
void show_short(short x) {
    
	show_bytes((byte_pointer)&x, sizeof(short));
}

//show_long
void show_long(long x) {
    
	show_bytes((byte_pointer)&x, sizeof(long));
}

//show_double
void show_double(double x) {
    
	show_bytes((byte_pointer)&x, sizeof(double));
}

void show_pointer(void *x) {
    
	show_bytes((byte_pointer)&x, sizeof(void *));
}


void test_show_bytes(int val) {
    
	//Prints byte representations of the three target types
	int ival = val;
	short stval = (short)ival;
	long lval = (long)ival;
	double dval = (double)ival;
	show_short(stval);
	show_long(lval);
	show_double(dval);
}

int main() {
    
	int test = 328;
	test_show_bytes(test);
	return 0;
}

win64 中long占4个字节

linux64 中long占8个字节