BOOL vs. bool

[iago]

I noticed that, when I'm using inline assembly, bool functions and BOOL functions don't behave the same.  Can anybody share some light on this?

Thanks!
-iago

[edit] I know that BOOL is typedeffed as an int, but bool seems to be native.  But how are they different?

[Zakath]

bool is a built-in data type.



sizeof(bool) == 1
sizeof(BOOL) == 4

That should account for most differences, I'd think.

[iago]

ah, so bool only counts as 1?  I figured they had left it as 4 for alignment.  

Thanks

[Skywing]

ah, so bool only counts as 1?  I figured they had left it as 4 for alignment.  

Thanks

It may be padded to 4 bytes depending on how and where it's used.  In the case of function return values, though, typically only al will be set for x86.

[Yoni]

Also, bool can be either true (1) or false (0), it cannot receive any other values. BOOL can receive any long/doubleword value and this is sometimes sloppily done in Win32 API. Examples: GetMessage return value, and the return value of WM_CTLCOLORSTATIC and its friends.