Using char array inside union

Question

I\'m able to print the address and values of ints but not the chars of the union.Why is that so

#include 

using namespace std;

union Endian         


        

Answer 1

Strictly speaking, the behaviour of your code is undefined. Contrary to what I said earlier, the behaviour of the code is not undefined (I think it's implementation-defined). See https://stackoverflow.com/a/1812932/367273 for an explanation.

What happens is that &e.c[0] is of type char*, and therefore gets printed as a C string, not as a pointer. The string is either blank or consists of non-printable characters, so you see no output. A similar thing happens to e.c[1], except that it's a single char and not a string.

When I initialize e as follows:

e.i = 0x00424344;

the last two lines print DBC and B respectively (this exploits the fact that on my machine, int 32 bits wide and is little-endian).