Delphi 6 Exe on Vista: Problems with GetWindowText - delphi

I have an exe file compiled with Delphi 6 under Windows XP that uses a combination of EnumWindows and GetWindowText to find a window (not belonging to the exe itself) with a specific title.
The behaviour is as expected under Windows XP. On Vista computers however, it doesn't seem to work.
As the mentioned Delphi version doesn't run on Vista, I cannot change and test this directly.
However, I will try to create a modified exe on the XP computer that outputs some additional data and copy it to the Vista computer.
I would just like to ask whether anybody has any information whether there are specific problems known with exe files compiled with Delphi 6 running on Vista regarding EnumWindows/GetWindowText.
The exe uses EnumWindows and GetWindowText to find the handle of a certain window in order to then parse the title of that window in a timer event. The window title is the application name plus the name of the file opened in that application (if any file is opened). The Delphi exe analyses/uses this file name, does something with it and behaves in a certain way.
On Vista the expected behaviour does not appear, thus I presume that the window handle is not found cause GetWindowText does somehow not return the text. Another reason of course could be that EnumWindows does not work properly and the window handle of the window that the exe is looking for is never send to the EnumWindowsProc.

Assuming that there has been no change in window title from XP to Vista, there's not much that can go wrong here. I'd hazard a guess that the problem is due to UIPI. This is part of the security enhancements of Vista and it means that processes can only send messages to other processes that have equal or lower integrity level. Is this other process running elevated?
Other than that your best bet is to run this under the debugger. Delphi 6 most certainly does run on Vista. It was written before UAC and so doesn't get on well with having no rights to write to its install directory. So, install it to somewhere in your user profile or C:\Delphi6 – basically anywhere that standard users have write access.
Finally, don't fall into the trap of running Delphi elevated. This will confound the UIPI issue if indeed that is an issue here.
Good luck!

Related

Is there any way to catch the error if loading a dll cannot find a dependency?

I am writing a Windows 32 bit program that can use one of multiple possible dlls. So it tries to load each dll in turn, using SysUtils.SafeLoadLibrary and if loading succeeds, it uses that dll.
Unfortunately some of these dlls are statically linked to other dlls. These dlls may be missing from the computer. In that case I get dialog telling me
[myprogram]: [myprogram.exe] System Error
The program can't start because [some dll name] is missing from your computer. Try reinstalling the program to fix this problem."
After pressing the OK button on that dialog, the program gets the error code and tries one of the other dlls which then works fine.
Rather than showing that dialog to the user I want my program to silently ignore it.
How can I accomplish that?
In case it matters: My program is written in Delphi 2007. The Windows version is Windows 8.1, but the program should also work with other Windows versions >= Windows XP.
I have tried SetErrorMode(SEM_FAILCRITICALERRORS) but it did not make any difference.
SafeLoadLibrary sets the error mode to the value that you provide as an argument, and then restores it after the call to LoadLibrary returns. Most likely you are not supplying a value for that parameter, in which case a default of SEM_NOOPENFILEERRORBOX is passed. In that case it is probably disabling SEM_FAILCRITICALERRORS which would explain the behaviour that you see.
You could solve the problem by passing SEM_FAILCRITICALERRORS every time you call SafeLoadLibrary. Or, perhaps better would be to pass the current error mode. However this is hard to obtain. In Vista and later you can call GetErrorMode. But in older versions you have to do this:
ErrorMode := SetErrorMode(0);
SetErrorMode(ErrorMode);
Because this is a process wide setting, you have a window of opportunity between the two calls to SetErrorMode, for multi-threaded applications to be caught out.
Frankly, I believe that you should call SetErrorMode exactly once in the lifetime of a process, at startup. With that in mind, I would shun SafeLoadLibrary.
If you wish to take advantage of its other function, namely to protect against changes to floating point control state, then you should implement that functionality yourself, in my opinion.

Delphi 2007 (CodeGear Delphi) locks EXE after link - (Win7 x64)

Delphi 2007 sometimmes holds a handle to the EXE it's linker makes. Sometimes it works fine. But other times it's a whole day saying: "Cannot make EXE file" or something similar when trying to compile or build a solution.
When I try to launch EXE made from Delphi it says that another process is holding the file. Going to "unlocker" says: bds.exe. Even if I unlock it I must rename it to eg. app1.ex_ and copy it back to app1.exe. But still Delphi is holding the handle to that .ex_ file.
Needless to say it makes debugging (or even running) and developing quite slow: having to deal with locked exe...
Any suggestion? Workaroung or fix available - I've been looking for it but can seem to find it: I'm sure others have the same problems (I've seen it) - is there any fix for this?
env.: Win7 Ent. x64, Delphi CodeGear 2007
Thanks!
Going to "unlocker" says: bds.exe. Even if I unlock it I must rename
it to eg. app1.ex_ and copy it back to app1.exe. But still Delphi is
holding the handle to that .ex_ file.
Based on the fact that renaming file causes the BDS.exe to "hold the lock" of renamed file I seriously doubt the BDS.exe is actually the one that is holding the lock. If BDS would be holding the lock on that file you wouldn't even be able to rename it.
So I would seriously suspect that your AntiVirus software might be behind it.
I even remeber having similar difficulties years back using Delphi 7. The cause then was ma AntiVirus software (Nod32 version 2). First workaround I was unsing was to simply delete the application exe file prior compiling, but later I simply added entire Folder into the AV residental protection ignore list.
So try adding your project folder into ignore list and see if it solves the problem.

Application portablity between Windows versions

I have an Delphi 7 Application that uses Halcyon dbf component. It works well in Windows ME.
Unfortunately in Windows XP data aware controls which are bound to Halcyon xBase Engine do not behave correctly. In addition pack command almost hangs the application. I tried compiling in XP. But no joy. Does that mean that API calls work differently? May be Data types mean different things....
Thanks for all help
A well written Delphi 7 application will work on any version of WIndows from 98 onwards. If you have managed to make an application that doesn't work on XP, then you should debug the problem on XP, not recompile and then give up. (no joy!? what? you're done already? Is that how you troubleshoot and debug?).
For posterity I should point out that if you change Delphi versions then of course, some things change. For example, If you build your Delphi application in Delphi 2009 or later, it will work properly on Windows XP, but not on Windows 98 or ME any more. But if you build your application using the same version of Delphi, why would you expect any changes in the application's bugs?
As David says; Rebuilding your application on a different computer, from the same code, and with the same compiler, produces the same binary. If you have a fundamental problem on Windows XP it is because you made a mistake in your code somewhere.
In general, windows 98/ME to 2000/XP was an easy transition, but that was a decade ago.
The only API I remember that was in Windows 98/ME that was not in XP, was the Windows 98 text-to-speech API which was removed and replaced with a different API in XP.
I believe your confusion is that windows contains something that affects Data Aware controls. It does not. Data Aware Controls are a purely Delphi thing, and they are not a part of Windows XP, they are 100% implemented inside Delphi. If you have some funny custom control that is badly written, perhaps it might not work. We have no idea what your code contains, and you haven't even described the nature of the failure.
You need to provide more information, or this question should be closed as unanswerable, or too localized. (My app doesn't work! Help! No other info given.)

"exe has encountered a problem and needs to close" message when exe is run. Runs OK on Dev machine

This is occurring on 2 machines that are both running Windows XP Pro SP3, yet it runs OK on my development machine within in or outside the Delphi IDE.
Running Windows XP Pro. Exe compiled under Delphi 2010.
When I run the exe I get the Windows Reporting error "Neopos.exe has encountered a problem and needs to close. We are sorry for the inconvenience"
I know it is happening somewhere in the form create of the main form.
Application.Initialize; //Runs this
Application.CreateForm(TfmMain, fmMain); //FAILS HERE
It does not get to: procedure TfmMain.FormCreate(Sender: TObject); in the Main Form and I don't know how to track down this error and debug it.
What happens between: Application.CreateForm(TfmUDF, fmUDF); AND procedure TfmMain.FormCreate(Sender: TObject) in my main form.
How can I trace this to find out what the hell is causing the Windows Error.
Of course the Windows Error report contains a long listing of information. Where can I look in that to find the cause or at least a clue on the cause of the error.
This error has now stopped all development work (and ruined my weekend) so I urgently need to fix this.
The most straightforward route to take would be to include a product like MadExcept or JCL Debugger into your application, to get a full call stack (including line number) of the point of failure. We've rolled our own years ago, and it has been a tremendous help in situations like this.
One alternative, but lots more cumbersome, would be to generate a MAP file from your project, use MAP2DBG to generate a .MAP file, and use the Windows Debbuging Tools to get about the same information. This approach is a lot more hardcore, and only advisable if you really want to learn a lot about the internals of windows debugging (and enjoy working with arcane tools).
Another alternative would be to attach to the failing application from your development environment using Remote Debugging. Only applicable if you have a fair amount of control over the failing machines.
#user576639, here are some debugging ideas:
Look into the System's Event Viewer
If you got the exe has encountered a problem and needs to close chances are you'll find something about it in the System's Event Viewer. That should be your first step.
Any special DLL's required?
Do you need MIDAS.DLL?
Are you using an database engine? Does it require some sort of client library?
I'm talking from experience here: My development machine obviously has all the libraries I might need. Most of my clients also have most of those libraries because they have my software installed. At times I put out small helping applications that don't go throw extensive testing and they fail to work on SOME machines but work fine on other machines. Why? I used TClientDataset and forgot to include MIDAS.DLL with the application; Or the application is trying to access a Firebird SQL server but the user doesn't have Firebird client library installed.
Printer driver issues
Boy I hate Delphi's printer handling. Also hate buggy printer drivers, haven't made up my mind about what's worst. If you have something on your main form that might be requesting information about the default Windows printer (example: an REPORT) give this a try: Install an sane/simple printer and set it as the default printer. If the user has Office 2007+ installed, set the "Microsoft XPS Document Writer" the default printer.
I have seen bad printer driver + delphi issues manifest themselves with the "exe needs to close" symptom.
Prepare an special build of your application
If you got this far without fixing your issue it's time to create an special build of your application that's capable of providing more information. First of all I'd try adding this to your DPR file; Don't know if this is still useful for Delphi 2010 but it did help me see some early exceptions with a Delphi 7 application:
function HandleUnhandledException:integer;stdcall;
begin
Result := 1; // 1 = EXCEPTION_EXECUTE_HANDLER
end;
// and then immediately after "begin" in your DPR file:
begin
SetUnhandledExceptionFilter(#HandleUnhandledException);
// ... the usual stuff goes here
end;
Add some ShowMessage-s to your Main Form's code, in your OnCreate handler (if you have one), in your Create constructor (again, if you have one). If you're adding an ShowMessage to your Create destructor, make sure it's after the "inherited" call. This will help pin-point how far the loading of the form goes before it fails.
If all else fails...
Create a new, blank form; Make it the new Main Form (so it's initialized before your former Main Form). Test it on the client's machine - does it show up? It most likely will, if it doesn't you've got some serious problems.
Start copying the components from the former main form to the new main form; Only the components need to be copied, not the code: Your error is probably caused by some component failing to initialize properly. Make sure no component has "Active=True"! Copy the components in small batches, test often. If you spot the component that causes your form not to load on the client's computer, tell us about it and we'll try to help.
If you manage to get all your components on the new form, write an OnCreate handler that sets Active := True for all the components that need that. Did that fix the issue?
If you got this far then all the components you used on your main form can load properly. The problem's related to YOUR CODE. Start copying all the code from your old main form to your new main form, in small bits, and test. You're bound to find the peace of code that causes your application to stop loading.
Use dependency walker to see if you're missing a required DLL.
You can use information from system reporting (your error and suggestion to send it ) with Error Report Grabber ( http://www.maxerist.net/main/soft-for-win/err-rep-grabber ). I developed this tool when I desperately needed to track a error that appeared very rarely so almost non-reproducible. It helped me to track the information from stack to find actual place in the code.
The tool works only on XP (MS removed this dialog in Win7 and probably Vista), but I see that your cases are XP so this can help.
UPDATE: if you're not familiar with assembler and everything, this can work like this.
You should compile you program and don't change anything. Save the report on a bad machine, copy the file to your developer machine and open to view the contents. Look at the stack of your main thread in the report and find numbers more than $00400000, they're usually the addresses inside the procedures that called some other procedure and wait for return. In your developer machine, start the program and stop at any line, open CPU Window and on the main list with assembler instruction right-click and choose go to address, enter this address. You will see other assembler lines, but wrapped with pascal constructions you can probably recognize as yours
Thanks a lot for the help.
In the end I reverted to a recent backup and traced it down to a particular form.
I did not actually find the error, which is a bit worrying, but in any case I am back up and running (phew!!)
I made the error to occur on my development machine also, when, and only when, I use my install program (Inno Setup) to compile a setup.exe and which installs the exe as well as installing postgreSQL. Seems really strange, as though there is a problem with the setup compiler. In any case I have not seen the error again. I guess it will remains a mystery, like women.
In Delphi withing debugging options select debug dcu's, this will allow you to debug into the Delphi source code for TForm and its descendants and you may be able to track down a more likely culprit.
Set a breakpoint on
Application.CreateForm(TfmMain, fmMain); //FAILS HERE
and then step into the code to see where the issue is.

Compatibility on WinXP and Vista

I developed an application using also third party components (developed on D7, WinXP).
When I deploy this application on XP everything works fine. When I run it on Vista, the application cease to work properly:
Toolbuttons on Toolbar does not size equally, when I switch visibility on/off, thats why (third party) skins are not properly nested and then it looks ugly. It bothers, it's annoying but it is not fatal as the next point.
Third party text processing component cease to write. I wrote some routines, which allows writing on this component under certain circumstances. It was a big shock to find out, that I can not write anything (probably these routines return false for writing, but I do not see any reason, why on XP it should work fine, but on Vista not).
The application runs (at last), but not in the way, like it supposed to !!!!
I would like to debug it, but how?
Should I install Delphi 7 on this problematic Vista computer and compile project on it? (this is it, what I am going to do...)
Is it problem of third party components?
Is there any possibility to use some compiler directives to ensure, that application will run on Vista flawless ? (be honest I do not know if Vista is to claim in general).
Is Delphi 7 too old for Vista?
NOTE:
When I run the same application on Win98, I get error message about invalid floating point operation...
Has anybody solved such problem?
Thanks
If Delphi 7 is compatible with Windows Vista, it only really means one or both of the following:
You can run Delphi 7 on Windows Vista
Delphi 7 can be used to write programs that can run on Windows Vista
It does not automatically mean that
All programs I create in Delphi 7 runs on Windows Vista
All programs I create in Delphi 7 runs properly on Windows Vista
Let me give you an analogy: That you can use a hammer to get a nail into your wall without hurting yourself does not mean that no matter what you do, you won't hurt yourself.
If your program, either in your own code, or as part of the third party components you use, use parts of Windows that has changed or possibly even been removed (although that's far less), then you need to fix your program, there's no way around it.
There's no silver bullet either, so no compiler directives or whatnot. The most I can think of is that perhaps Windows Vista has some compatibility settings for the shortcuts that might turn on some XP-compatibility layer in Vista that fixes the particular issues you have.
However, the only long-term solution is to change your program so that it is properly compatible with Windows Vista, and probably Windows 7 as well.
Since you say you're using third-party components, have you verified if the particular versions of them that you use happen to be Vista-compatible? You need to go check on the websites of the authors to find that. Perhaps it can be solved by simply upgrading those components.
However, it might also be that you need to make changes to your own code.
The best way to move forward is to install Vista and possibly Windows 7 and start debugging to try to find the underlying cause of the problems.
Note that just installing Delphi 7 on Vista and recompiling will not fix anything. The compiler does not produce a different program if you compile it on a particular Windows version. Only changes to the code will apply the necessary changes.
The easiest solution is to make sure your Delphi version and 3rd party components are Vista compatible.
Delphi versions since 2007 are.
Recent TMS, DevExpress and Raize components are.
The hard solution is to do all the changes yourself.
Be prepared to modify the VCL sources from 2002, carefully modify them to bring them up to Delphi 2007 level.
Then do the same for your 3rd party components.
--jeroen
I never really investigated, but I noted that in some apps that I have, in all skinned modes (XP-teletubbie, and Vista/W7 non classic) I had paint artifacts with all delphi verrsions if I put buttons and labels directly on tframes or ttabsheets.
The problems went away when I inserted a panel inbetween.

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