Thread: What does this struct for ?

I forget where I got this snippet from.
Anyway, here's the code

Code:

struct foo {
	char ch : 8;
	int aaa : 2;
	long bbb : 3;
};

I don't think it's for creating arrays ...

ch goes from -128 to 127
aaa from -2 to 1
bbb from -4 to 3

char does not go from -127 to 127 I think. It is a char and it is unsigned. ??

The integer arithmetic can be either two's complement, ones complement or sign-magnitude (though most modern machines use the first). The latter two have a symmetric range, the first has one extra on the minus side. Whether a char is signed or unsigned depends on the compiler (unlike other integral types which are signed by default), so to guarantee one or the other it's necessary to specify signed or unsigned explicitly.