I have a program built with VB6 and using some 32-bit DLL's. Will this program run on a 64-bit machine? This page suggests that it should run fine on the Windows on Windows layer, but what about the DLL's?
Yes, both the VB 6 program and the DLLs will work just fine on a 64-bit version of Windows.
Since both are 32-bit, they will run under the Windows-on-Windows 64 (WoW64) subsystem, which effectively emulates a 32-bit operating system on the 64-bit versions of Windows.
I've run many such programs myself with nary a hitch.
Beyond Explorer extensions and kernel mode drivers (neither of which you've written in VB 6), any compatibility problems that you might experience are almost certainly the result of bugs in your own code, which are easily fixed upon detection. Ask more questions about that when you find them.
Are the DLLs built with VB6 as well? Or are they native?
If you are dealing with 100% VB6, then in my experience, yes they tend to run with minimal problems (I maintained a number of plug-ins for another program that were mostly implemented as VB6 COM components, around the time that Windows 7 came out).
It will all of course depend on what libraries your code is using, whether or not you are accessing locations such as %PROGRAMFILES% etc, calling code in native libraries. These things can cause small problems but it is possible to work around them.
Microsoft are still supporting the VB6 runtime on 64-bit windows
Yes, it works, and if you have any problems they will help you.
Related
I'm developing a network redirector using RDBSS.
In our network redirector volume, a executable file which is packed from Inno Setup(Open source packer) can not be run.
When we do double-click the file in Windows Explorer, the Explorer shows this messagebox.
It works well on 32bit Windows. Only 64bit Windows is problem.
I guess it is related with npdll or MUP.
We have implemented npdll, and I thought it doesn't have any bug now. - Of course we also have npdll 64bit version.
Other executable files and any files work well for both 32 and 64OS.
If we run this file in 64bit Windows SMB volume, it runs fine.
So, I'm pretty sure some our codes have a bug.(npdll or redirector driver)
Could you guess anything about this?
P.S Is there a good document describing how MUP works? If you know, let me know please.
Thanks.
The other executables which work, are they 64-bit or 32-bit?
If only 32-bit processes (like InnoSetup) fail, could it be that you need to install both the 64- and 32-bit versions of your DLL on x64 systems? That's required for some DLL types (e.g. video codecs) if you want their functionality to be available to all programs, but I'm not familiar with RDBSS and thus don't know if it applies in this case.
how can i make a device input and output control program on windows 7??
Previously there was an option called debug where we wrote our programs. but as far as i know this feature is no more in windows 7. how can i do assembly on windows7??
You can use an assembler such as NASM, YASM, etc., or MASM which is free with Visual Studio Express (for non-commercial use).
I was thinking of Grdb, but it is only available for 32-bit, as a debug alternative.
I'm not sure what you are asking for with your first question, so I cannot answer it. I hope the above answers your second question.
It sounds more like you want to write a device driver? If so, download the Windows Driver Kit from Microsoft.
You can use this to write your driver in assmbly code if you wish. Be aware that this is NOT a trivial task.
What may be a better idea for you is to either install the WinXP virtual machine feature that comes with Windows7, or install WinXP/98/95 on an old machine, and do your coding on that. Under those OSes the driver model was simpler, and you could easily access the interrupts directly and/or easily elevate yourself into Ring 0 if you needed to.
Debug is available on Windows 7 32 bit, but not 64 bit.
Well, to begin with, I'm using Visual Studio 2008 on a 32-bits Windows XP system. I have a second 32-bits Vista system but that's not used for development.
I just ordered a new development computer which will use 64-bits Vista. (Don't want Windows 7 just yet, but will probably upgrade to Windows 7 in two years from now if it has a good market value.) (Btw, Intel Xeon Quadcore, 12 GB RAM, 1.3 TB diskspace over 2 disks.) I know that most 32-bits applications will work just fine, including VS and several others. I'm not too worried about this anyways. I also do development with Delphi 2007 but am not worried about this either. But I do want to take this in consideration:
On this new 64-bits system I can start developing 64-bits applications. This is new for me, so what are the most common pitfalls that I need to avoid when I start to develop new 64-bits applications? For example, datatypes that are of a different size, a file system that might be different, special 64-bits functions that I need to be aware of, possible conflict when I have to combine my 64-bits code with 32-bits assemblies, etc.
(I know one already: when developing web applications, I need to make sure my webhost is supporting 64-bits applications, else it's no use... Apparently, IIS doesn't seem to be able to support both 64-bits and 32-bits applications, so that's one pitfall.)
I'm not going to port 32-bits applications to 64-bits applications. I just want to create new 64-bits applications. From scratch! So without any 32-bits history. I've also read about this unanswered Caveat question but that's more about migrating. I won't migrate anything.
Deployment headaches at least for desktop applications.
Special Folders are different for some reason.
Edit and Continue in Visual Studio only works when compiling to 32bit.
You could find some obscure issues which could take forever to work around.
I've been using a 64-bit Vista system since November, with very few problems. The worst so far is that in Visual Studio, to debug a Script Task in SSIS, you have to tell it not to use the 64-bit runtime.
I'm migrating my development workstation from 32-bit Vista to 64-bit Vista.
The production platform is 32-bit Windows Server and SQL Server 2008.
Does anyone know of any issues with migrating the code base?
EDIT:
the system consists of web forms, c# code, stored procedures.
there is also ajax.net, ssrs, ssis, and dynamic reports/graphs from dundas.
however, i think other users might appreciate any lessons learned or feedback in general regarding this move.
FINDINGS:
As of Jan 24, 2009
Checkpoint VPN does not support Vista 64 (actually it seems that very few do)
Cropper utility required special download and rebuild to work on Vista 64 (Cropper looks very nice, but it lacks scrollable window capture)
The lack of support for Vista 64 made it not worth while for me. I wish someone would have mentioned the lack of VPN support, but there is currently no vpn vendor that supports 64 bit clients.... So be forwarned - as of 1/28/2009 - using Vista 64 is not a good option for those of us who need vpn.
I have done exactly this - migrated my workstation to Vista 64 whilst still deploying code to 32-bit Win2008 servers.
Generally, your biggest problem will be the WOW64 emulation layer - which means that 32-bit processes and 64-bit processes see different versions of the same resources (registry keys, system folders, and so on.) In .NET, there's an enumeration System.Environment.SpecialFolder which will give you safely abstracted access to Program Files, Application Data and other potentially risky system folders. You'll also need to force IIS to run in 32-bit compatibility mode (it can't run 64-bit and 32-bit web apps simultaneously) - instructions at http://support.microsoft.com/kb/894435
There's nothing insurmountable, though - I'm successfully compiling COM-visible .NET assemblies on Vista x64 (setting the compiler to target x86 CPUs), and then deploying them alongside ASP.NET and legacy ASP code running 32-bit COM objects on a 32-bit server, and it's all working very well. There's some notes you might find useful posted on my blog; biggest headache I encountered personally was that 32-bit applications (including my favourite text editor) can't see C:\Windows\System32 any more... but even that's easy enough to work around.
Don't use hard coded names for system folders.
(a bad idea anyway)
I have come across one issue with Vista 64:
Program Files
Program files may be stored in Program Files x86 or in Program Files you may have to code around this if any of your code makes assumptions about where programs are stored - even if you have done the right thing and used environment variables, as there are 2 locations there are now 2 different environment variables. You need to know which of these your app will be installed in, which will be different if you target any CPU from if you target x86.
I had much trouble with adding 3rd party 32 bit ISAPI handler to IIS on 64 bit w2k3 server (php) I had to make IIS run in 32 bit compatibility mode. If it's all managed I can think of no serious problem though.
While it's my understanding that there's no fundamental reason a program written for 32-bit hardware / OSs not to run on 64-bit hardware / OSs, in practice, I've found many programs intended for 32-bit versions of Windows that will not work on 64-bit versions of Windows. Examples include a number of popular security utilities (most products from Norton and Check Point's Zone Alarm) and several games (I've been trying to get Grand Theft Auto 4 to run for a few weeks now, but to no avail - of course, that might be related to any number of other problems related to GTA4, but that's neither here nor there).
I've heard that a program's incompatibility might result from something as simple as not wanting to run from the "Program Files (x86)" folder, but what are some of the other reasons? Why would a virus scanner or firewall written for a 32-bit system not run on a 64-bit system? Why would a game not run when everything is theoretically backwards-compatible?
There is a lot of misinformation on this thread.
When a 32-bit application is run on 64-bit windows:
Most of the compatibility problems come when the application tries to install a kernel-mode driver. A 32-bit driver can't be installed on the 64-bit OS. This is amost certainly the problem with a firewall. It's trying to hook into the TCP/IP driver stack.
THERE IS NO EMULATOR! The 32-bit object code is executed by the cpu completely natively at full speed.
There is no support for old 16-bit code. This broke a lot of installers.
Accessing the right folders is generally not a problem. When a 32-bit program opens a file in, say %windir%\system32\, the OS automagically redirects it to %windir%\syswow64. The same for certain parts of the registry. There are a few potential gotchas here, but they're generally along the lines of assuming that various WINAPI Get...Directory() functions return the same strings that they did in Windows 95.
Whether it was compiled 10 years ago or just yesterday, then C/C++ pointers are still 32-bits (4 bytes) and all of the code that just assumed that -- including SendMessage()! -- still works. The 8-byte pointer issue doesn't come into the picture until you start converting to 64-bit compilers.
The best explanation I've found is offered here which basically says 32-bit programs are run on an layer of emulation which doesn't allow the system access you'd get from native programs run in a 64-bit environment:
http://blogs.msdn.com/oldnewthing/archive/2008/12/22/9244582.aspx
I would assume this means that problems with programs like GTA4 come from the layer of emulation not producing the expected results found on a 32-bit native system. This is why you keep seeing Microsoft release compatibility updates all the time.
Here's what the MSDN has to say about the matter:
http://msdn.microsoft.com/en-us/library/bb427430(VS.85).aspx
Drivers are a different story that programs:
http://support.microsoft.com/kb/896456
Zone Alarm uses a special 32-bit driver created by Check Point to do the monitoring. This is probably what's creating the issue with that application. As for Grand Theft Auto 4? I have no idea.
There can be any number of reasons.
Any application which is programmed ad a low level might be expecting 32 bit register. The Zone Alarm driver posted by novatrust is a good example. GTA4 might be using assembly to improve performance at several points which might result on anything or even simply assuming 32 bits on C++. For example take the following code:
struct GPoint
{
int x;
int y;
}
// Array of twenty GPoints
GPoint[] myArr = malloc(20 * sizeof(GPoint);
GPoint* myPointer = myArr;
int index = GetIndexAffectedPoint();
// Invert X and Y for the point
myPointer += 8*index;
swap(myPointer);
I know the example is pretty naive but anyway, in that code you are assuming you're struct is 8 bytes long (4 bytes of the x integer and 4 bytes for the y integer) but in a 64 bit system is actually twice that long so you'll end up swapping the wrong point... things like that happen a lot on low level languages, specially when trying to improve performance...
Security applications are a bad example. They all perform unsupported things against undocumented things. Changes between one 32-bit version of Windows to the next are enough to break them, nevermind moving to 64-bit.
That said, there are some compatibility shims that fixup your code on 32-bit that won't when the app is 64-bit. This is because Microsoft assumes you've tested it on 64-bit.
One resulting gotcha is with .NET applications. When running on a 32-bit system, the exe is jitted to 32-bits - where there are compatibility shims to fix your bugs. If your customer happens to be running on a 64-bit system, the executable will be jitted to 64-bits, where those compatibility shims that were protected you from yourself are no longer present.
Chris Jackson had a nice blog entry about this: Shimming Applications on Windows Vista 64-Bit
The problem is probably drivers. With games, it's probably some kind of slimy DRM scheme. Try getting the no-CD crack for the game so you can run it without DRM.
32-bit to 64-bit Migration Considerations
EDIT: Alternative link
If you are using the file system or the registry, make sure that you access the right folders. As a x86 program you will probably want to access "Program Files (x86)", "SysWOW64", "WOW6232Node" and such folders instead of the x64 ones.
Products with x86 applications like Norton and Check Point's Zone Alarm fail to run their x86 driver, as the driver needs to x64 to be able to ran by the operating system.