I'd like to use some functions that are only available in Windows 7 or higher in my application but I also want my app to remain compatible with Windows XP. The app should check at runtime if at least Windows 7 is available and offer some advanced features (like Media Foundation support) in that case.
Is the only way to do this to manually check for Windows 7-only DLLs using LoadLibrary and then importing all the functions I need using GetProcAddress()? This would be very inconvenient but I don't see any other way. Statically linking against Windows 7+ DLLs will cause the application to refuse to start on XP because of missing DLLs so this won't work. But doesn't the Windows SDK offer some more convenient technique for programmers who want to remain compatible with older Windows versions and optionally use features of newer Windows versions?
Note that my application is written in plain C so I'm looking for a solution in C.
Don't ever check for OS versions. Check for available features instead.
The most convenient way to keep your code compatible with earlier versions of Windows while still allowing it to opt-in to newer features is to use delay-loading of modules (see Linker Support for Delay-Loaded DLLs). This allows you to benefit from import resolution as you would with compile-time dynamic linking, yet allows you to respond to import failures at runtime.
There are 2 options:
LoadLibrary / GetProcAddress. It is not so inconvenient - you can define and assign function pointers and use them like normal functions.
Compile 2 versions for XP and 7. The installer chooses the right executable or XP version is started by default and it runs second executable if OS is Win7.
I have Windows 2003 server, with executable built on VC6. I would be needing to check the compatibility of the executable on Windows 2008 server (both servers 32 bit). I know that I need to check for ABI compatibility for these two versions.
How do I confirm that there is ABI compatibility for any two versions of a OS? Or does Windows release the ABI compatibility as part of product document?
Is there any other set of consideration to be taken care apart from ABI compatibility?
Windows maintains binary ABI compatibility between different versions. This means that programs do not need to be re-compiled for different versions.
However, this is not enough to guarantee that a program will run correctly on a version that you have not yet tested. Some examples of possible problems:
You use a deprecated API that has been removed in a later version.
You use an API that exists only on a later version of the OS and so your program fails to run on an older version.
The OS changes functionality that breaks your app. The classic example of this was UAC in Vista. The ABI did not change, but some pre-UAC apps failed to run correctly under UAC.
The bottom line is that you do need to understand the theory behind binary compatibility. But that does not absolve you of the need to test. Make sure that you've tested your program on all supported systems. Or at least as many as you can reasonably manage to find.
See detailed analysis of changes in the Windows API on this page. The reports are generated with the help of the abi-compliance-checker tool.
I am trying to install Sheridan controls (ActiveThreed 2.01) on Win7 64-bit, but evidently it is a 16-bit installer so it won't execute.
What would be the best way to get round this problem?
Can anyone comment on whether http://homepage3.nifty.com/takeda-toshiya/msdos/index.html would be helpful?
It took me months of googling to find a solution for this issue. You don't need to install a virtual environment running a 32-bit version of Windows to run a program with a 16-bit installer on 64-bit Windows. If the program itself is 32-bit, and just the installer is 16-bit, here's your answer.
There are ways to modify a 16-bit installation program to make it 32-bit so it will install on 64-bit Windows 7. I found the solution on this site:
http://www.reactos.org/forum/viewtopic.php?f=22&t=10988
In my case, the installation program was InstallShield 5.X. The issue was that the setup.exe program used by InstallShield 5.X is 16-bit. First I extracted the installation program contents (changed the extension from .exe to .zip, opened it and extracted). I then replaced the original 16-bit setup.exe, located in the disk1 folder, with InstallShield's 32-bit version of setup.exe (download this file from the site referenced in the above link). Then I just ran the new 32-bit setup.exe in disk1 to start the installation and my program installed and runs perfectly on 64-bit Windows.
You can also repackage this modified installation, so it can be distributed as an installation program, using a free program like Inno Setup 5.
You can't run 16-bit applications (or components) on 64-bit versions of Windows. That emulation layer no longer exists. The 64-bit versions already have to provide a compatibility layer for 32-bit applications.
Support for 16-bit had to be dropped eventually, even in a culture where backwards-compatibility is of sacred import. The transition to 64-bit seemed like as good a time as any. It's hard to imagine anyone out there in the wild that is still using 16-bit applications and seeking to upgrade to 64-bit OSes.
What would be the best way to get round this problem?
If the component itself is 16-bit, then using a virtual machine running a 32-bit version of Windows is your only real choice. Oracle's VirtualBox is free, and a perennial favorite.
If only the installer is 16-bit (and it installs a 32-bit component), then you might be able to use a program like 7-Zip to extract the contents of the installer and install them manually. Let's just say this "solution" is high-risk and you should have few, if any, expectations.
It's high time to upgrade away from 16-bit stuff, like Turbo C++ and Sheridan controls. I've yet to come across anything that the Sheridan controls can do that the built-in controls can't do and haven't been able to do since Windows 95.
I posted some information on the Infragistics forums for designer widgets that may help you for this. You can view the post with the following link:
http://forums.infragistics.com/forums/p/52530/320151.aspx#320151
Note that the registry keys would be different for the different product and you may need to install on a 32 bit machine to see what keys you need.
I am mostly posting this in case someone comes along and is not aware
that VB2005 and VB2008 have update utilities that convert older
VB versions to it's format. Especially since no one bothered to
point that fact out.
Points taken, but maintenance of this VB6 product is unavoidable. It would also be costly in man-hours to replace the Sheridan controls with native ones. Simply developing on a 32-bit machine would be a better alternative than doing that. I would like to install everything on Win7 64-bit ideally. – CJ7
Have you tried utilizing the code upgrade functionality of VB Express 2005+?
If not,
1. Make a copy of your code - folder and all.
2. Import the project into VB express 2005.
This will activate the update wizard.
3. Debug and get the app running.
4. Create a new installer utilizing MS free tool.
5. You now have a 32 bit application with a 32 bit installer.
Until you do this, you will never know how difficult or hard it
will be to update and modernize the program.
It is quite possible that the wizard will update the Sheridan controls
to the VB 2005 controls. Again, you will not know if it does
and how well it does it until you try it.
Alternatively, stick with the 32 Bit versions of Windows 7 and 8.
I have Windows 7 x64 and a program that will not run. However,
the program will run in Windows 7 32 bit as well as Windows 8 RC 32 bit.
Under Windows 8 RC 32, I was prompted to enable 16 bit emulation
which I did and the program rand quite fine afterwords.
I had 32-bit software with a 16-bit installer that I couldn't unzip. I solved it with otvdm which allows you to run windows 1.x, 2.x, 3 programs on win64. In fact, otvdmw allows you to select the program to run (otvdm is command-line).
16 bit installer will not work on windows 7 it's no longer supported by win 7 the most recent supported version of windows that can run 16 bit installer is vista 32-bit even vista 64-bit doesn't support 16-bit installer....
reference http://support.microsoft.com/kb/946765
Bottom line at the top: Get newer programs or get an older computer.
The solution is simple. It sucks but it's simple. For old programs keep an old computer up and running. Some times you just can't find the same game experience in the new games as the old ones. Sometimes there are programs that have no new counterparts that do the same thing. You basically have 2 choices at that point. On the bright side. Old computers can run $20 -$100 and that can buy you the whole system; monitor, tower, keyboard, mouse and speakers. If you have the patience to run old programs you should have the patience to find what you are looking for in want ads. I have 4 old computers running; 2 windows 98, 2 windows xp. The my wife and I each have win7 computers.
I'm maintaining an old VB6 application, that uses some Sheridan 3D controls (SSPanel and SSTab, found in threed32.ocx and tabctl32.ocx).
Will this application work on a 64-bit machine (I guess the 32 in threed32 comes from the bit number?)
If not, what can I do to make it work?
It should run fine via WoW.
EDIT: Since you've clarified that it's a 16-bit application1, if it's a LOB application that absolutely must run then you could try Windows XP Mode for Windows 7 and later.
If you've got a copy of VB6 kicking around, try importing the project and compiling it at 32-bit.
Otherwise you might want to put the source code through the VB .NET project upgrade wizard and see how far you can get simply by targeting 32-bit.
1 Are you sure it's VB6? The only references to 16-bit VB applications were from VB4
We have an application we're trying to deploy on both 64 bit and 32 bit platforms. Is there a way to put both compiled versions of the code in the same binary, a la Apple and NeXT's fat binaries?
Ideally we could ship one .exe that decides upon execution which version of the code to execute. We're targeting Windows XP and later.
Process Explorer (was sysinternals, now owned by Microsoft) does this. It is a 32-bit application that detects a 64-bit environment, writes out another binary and deletes it on exit. http://technet.microsoft.com/en-us/sysinternals/bb896653.aspx
One approach is perhaps to supply a bootstrapping application that determines the architecture and chooses the appropriate executable to run. So basically the shortcut or what have you to your application simply starts the bootstrapper which in turn starts the appropriate application. This can be a little more tricky if your application is a Windows service.
The simplest approach would be to handle this by the installer - it would have two versions of each binary and copy necessary versions depending on which system bit-ness is at the target machine.