Little endian Vs Big endian

Question

Lets say I have 4Byte integer and I want to cast it to 2Byte short integer. Am I right that in both (little and big endian) short integer will consist of 2 least significant by

Answer 1

You should be aware that your second example

int i = some_number;  
short s = *(short*)&i;

is not valid C code as it violates strict aliasing rules. It is likely to fail under some optimization levels and/or compilers.

Use unions for that:

union {
   int   i;
   short s;
} my_union;

my_union.i = some_number;
printf("%d\n",my_union.s);

Also, as others noted, you can't assume that your ints will be 4 bytes. Better use int32_t and int16_t when you need specific sizes.