Windows Data Type Sizes - DllCall() / NumGet() / NumPut()

[jNizM]

4 | 4 when I use WinDef.h (but not sure why)

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CONST

A variable whose value is to remain constant during execution.
This type is declared in WinDef.h as follows:
#define CONST const

but all I found about const in WinDef.h is:

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typedef struct tagRECT
{
    LONG    left;
    LONG    top;
    LONG    right;
    LONG    bottom;
} RECT, *PRECT, NEAR *NPRECT, FAR *LPRECT;

typedef const RECT FAR* LPCRECT;

typedef struct _RECTL       /* rcl */
{
    LONG    left;
    LONG    top;
    LONG    right;
    LONG    bottom;
} RECTL, *PRECTL, *LPRECTL;

typedef const RECTL FAR* LPCRECTL;

[TheArkive]

That makes sense. If you keep the compiler set to x86, then the size of that would certainly be 4, ptr size on x86.

I imagine the sizeof value would be 8 on x64 (pointer size).

EDIT: i mean x64 in 2nd sentence, so changed it.

[TheArkive]

The size of any object that is referenced by pointer will always be pointer size, regardless of the size of the object that it points to. The actual size has to be determined by actually doing sizeof(real_object) such as sizeof(RECT) or sizeof(tagRECT).

[TheArkive]

@jNizM

I was able to verify size = 4 | 8 where typedef const RECTL FAR* LPCRECTL.

Just wondering if you were able to do the same? I used MSVC BuildTools (just updated this morning).

But I don't think this is a case for CONST. I still think CONST should be removed from the list.

[jNizM]

LPCRECT and LPCRECTL = 4 | 8
while the struct RECT and RECTL itself = 16 | 16

[TheArkive]

Yes indeed, I got that as well. I plan to compute struct sizes in a later version of ConstScanner. But I'll do this is after I'm able to catalog as many entries as possible in a specific context (currently WIN64 AMD64 Unicode context).

The calcs will be done by just analyzing types and doing basic addition, and obeying union rules (largest element). And of course I will verify with compiler as often as possible.

[jNizM]

Give you some ahk projects I watched long time ago. All about dllcall, structs and so on. Maybe something useful for you

- https://github.com/ahkscript/WinStructs
- https://github.com/HotKeyIt/_Struct (@HotKeyIt)
- viewtopic.php?t=31711 (@Alguimist)
- https://www.autohotkey.com/board/topic/69139-class-dllstruct-ahk-11/ (@just me)
- viewtopic.php?t=30497
- viewtopic.php?t=61987
- https://www.autohotkey.com/board/topic/4613-ahkstructlib-functions-for-use-with-structures-version-2/
- https://www.autohotkey.com/board/topic/25250-structparser-for-cc-structs/

there was one more (but cannot find it without my external drive atm)

[TheArkive]

Woah. That's a lot! Thanks for the links ... that will be helpful for me to either pick up where these projects left off, or to fill in extra data.

Thanks!