Hi,

The following program runs, loads the DLL, excutes the function, returns the correct value and unloads the DLL, but on exiting causes an exception:

Unhandled exception at 0x0040f9c0 in USBRelay.exe: 0xC0000005: Access violation writing location 0xffffffea.




The FT_STATUS is declared...
    alias uint FT_STATUS;

The function is declared...
    alias extern (C) FT_STATUS function(uint* lpdwVersion) FT_GetLibraryVersion;

The main program is...

module main;

import	std.stdio,
	ftd2xx,
	core.runtime,
	std.exception,
	std.c.windows.windows;


int main(string[] argv)
{
	string	dllFilename = "FTD2XX.DLL";
	uint	libVer;

	auto hDLL = enforce(cast(HMODULE)Runtime.loadLibrary(dllFilename));

	scope (exit) Runtime.unloadLibrary(hDLL);

	FT_GetLibraryVersion GetLibraryVersion = enforce(cast(FT_GetLibraryVersion)GetProcAddress(hDLL, "FT_GetLibraryVersion"));

	FT_STATUS rv = GetLibraryVersion(&libVer);

	writefln("Version : %0x", libVer);

	return 0;
}

I'm sure its something stupid but nothing leaps out from the screen.
Am I using the loadLibrary and enforce correctly?

Regards, Frank.

On Tuesday, 4 June 2013 at 14:06:29 UTC, Frank Fuente wrote:
> The function is declared...
>     alias extern (C) FT_STATUS function(uint* lpdwVersion) FT_GetLibraryVersion;

The calling convention is wrongly declared, it should be:

>     alias extern (Windows) FT_STATUS function(uint* lpdwVersion) FT_GetLibraryVersion;

From the header file[1] I can see it uses the WINAPI macro, which makes the function have the stdcall calling convention (extern(Windows) in D).

ftp://ftp.mn-net.com/Rapid_Tests/Software/USB%20DRIVER/FTDI_USB_32BIT/FTD2XX.H

On Tuesday, 18 June 2013 at 00:16:10 UTC, Andrej Mitrovic wrote:
> On Tuesday, 4 June 2013 at 14:06:29 UTC, Frank Fuente wrote:
>> The function is declared...
>>    alias extern (C) FT_STATUS function(uint* lpdwVersion) FT_GetLibraryVersion;
>
> The calling convention is wrongly declared, it should be:
>
>>    alias extern (Windows) FT_STATUS function(uint* lpdwVersion) FT_GetLibraryVersion;
>
> From the header file[1] I can see it uses the WINAPI macro, which makes the function have the stdcall calling convention (extern(Windows) in D).
>
> ftp://ftp.mn-net.com/Rapid_Tests/Software/USB%20DRIVER/FTDI_USB_32BIT/FTD2XX.H

Btw, apologies for the late reply.