CreateFile library error

[DSMan195276]

That's even more confusing. I am also using _unsigned long for functions concerning attribute returns.

Do I have to modify them as well?

You simply need to read the Microsoft documentation and understand the C++ types used. See the CreateFileA description.

DWORD

is a 32-bit integer, which in QB64 is a

LONG

.

LPCSTR

is a string pointer, and translates to a

String

in QB64 (passed by reference, but that's the default).

LPSECURITY_ATTRIBUTES

is a pointer (LP), so it should be an

_Offset

. And

HANDLE

is a typedef for a

void *

, so in QB64 it should be an

_Offset

.

As a separate question, is there a reason you're trying to use

CreateFileA

and other Win32 APIs in the first place? The best way to make your program cross platform is to simply avoid using any

Declare Library

or Win32 APIs, and just use built-in commands like

OPEN

to create files. If you're not comfortable understanding the C++ types then you're likely to just keep running into issues trying to use Win32 APIs. They're all intended for being used in C++ code, not QB64, you can call them but you need C++ knowledge to really do it properly.