I had to download a different version from a DLL, but now this new version requires 4 other DLLs, which I don't want to add into my package. Since I'm not even using them, it would be a waste of space.
Is it somehow possible to edit the DLL and make it ignore the missing dependencies which aren't even used?
I'm talking about libgd2.dll, and since the website is down, I was unable to find the old version of this library, so I had to download this newer version. Earlier I had bgd.dll, but now I can't find the old bgd.lib file anywhere on the web.
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I know this question is not specific to crypto++. But I compiled crypto++ on a Mac OS X using Qt. After building I see 4 files with the dylib extention:
libcryptopp.1.0.0.dylib
libcryptopp.1.0.dylib
libcryptopp.1.dylib
libcryptopp.dylib
What is the difference between them? Which one is actually used to compile against my application?
The multiple files exist in case your application needs to link to a specific version of it. Of course, you have just one version of the library, so it doesn't seem helpful, but consider these on my system:
libnetsnmp.15.1.2.dylib
libnetsnmp.15.dylib
libnetsnmp.25.dylib
libnetsnmp.5.2.1.dylib
libnetsnmp.5.dylib
libnetsnmp.dylib
Only .25, .15.1.2 and .5.2.1 are actual files, the rest are symbolic links for either. In your case, they're probably all symlinks except 1.0.0, so you case use either.
If you look carefully, there's just one actual dylib (libcryptopp.1.0.0.dylib) and 3 links to that one. These give you the version info for the library.
If you want to link to a specific version you can specify that, else if you always expect your app to work with the latest version, you can point to libcryptopp.dylib.
I have written a simple application using the GPhoto2 Framework, and this works so long as the framework is in the location where it was originally compiled. I would like to move this inside the app bundle, though, so it does not need separate installation, so I need to make it work relative to this main executable.
Unfortunately the framework is not an Xcode project. It uses a script to build, so I cannot simply change the installation directory build setting, which is the solution that I have frequently seen while searching for an answer. Being quite new to Xcode and Mac programming it is also beyond my abilities to know how to convert the framework into an Xcode project.
The other advice I came across was to use install_name_tool to update the library ID and dependencies, replacing the absolute paths with ones of the form "#executable_path/../Frameworks/GPhoto2.framework". The framework is not a single binary, but contains a number of .dylib and .so libraries, but updating all of these has only been half successful.
I have set Xcode to copy the framework into the app bundle when it builds it. Then if I remove the framework from its originally compiled location the application fails to load, with the report generated by OS X saying the libgphoto2 library can no longer be found, as to be expected.
If I then use install_name_tool to update the references in all of the framework libraries inside the app bundle, and also in the app binary itself, then the application will load but fails to find any camera connected. Using otool I am able to verify that all references have correctly been changed.
But if I replace a copy of the framework to its original location it then works properly again, recognizing connected cameras, regardless of whether that framework uses relative or absolute locations. Clearly it is still looking at this location despite loading. I have even tried removing each of the individual library files from the framework in its original location in turn to see if the problem was just the result of a dependency in of these, but no matter which is missing the app will not work.
Incidentally, if I build the app using an updated version of the framework, it fails saying it cannot find the library "#executable_path/../Frameworks/GPhoto2.framework/prefix/lib/libgphoto2.2.dylib"
Am I doing something wrong or missing a step, or is what I am trying to do impossible for frameworks created outside Xcode?
In case someone comes across this future, the answer to my question was that I was doing nothing wrong. The problem was that the .so files were being loaded by libtool ltdl, at it requires absolute paths so these were being set at build time.
I patched the files gphoto2-abilities-list.c and gphoto2-port-info-list.c so that at runtime it would combine the relative library paths with the executable location. As a result I also needed to increase the FILENAME_MAX constant to allow it the mail application to run from, for example, the Desktop. But this, along with the use of install_name_tool allowed me to add GPhoto2 as a framework inside my application without needing any external dependencies.
The final problem of not being able to build my app in XCode with the framework after using install_name_tool remained, but for that I just used the original framework build, then after compilation I updated the references in the copied framework at the same time as I updated the ones in the main executable.
I am building a win32 executable. The compiler is the latest version of MinGW. The library dependencies are GLUT and libpng.
I first tested on a windows 7 machine, and had to obtain libpng3.dll and freeglut32.dll. However, on XP, I had to (in addition) acquire zlib1.dll.
The XP machine was a VM with a fresh install, so I suspect a fresh win7 machine may also be lacking zlib1.
My question is how do I go about finding out which dll's I need to distribute? How do I know, a priori, which dynamic libraries are needed for my program to run on a particular system? I suppose this is what installer programs are for... I'm guessing that what the installer does is look through the system to find out which dependencies are unsatisfied, and then provides them. So this way if I were to distribute my program I could check if the user's machine already has zlib1.dll, and I won't install zlib1.dll if it's already found in the system directory. However I never found a document that said to me specifically, "libpng requires zlib", and so, until such point as I tested the executable on a machine lacking zlib, I was unaware of this dependency. How can I create my dependency list without having a fresh install of each version of every operating system to test on?
One idea I have is to decompile the executable, or through some method examine the linking process, to find all the libraries that are being linked at runtime. The problem now becomes figuring out which of these are supposed to already be there, and which of them I could be expected to provide in the distribution.
edit: Okay, I looked, and the installation of libpng I downloaded did provide zlib1.dll inside its bin directory. So not including it is pretty much my fault. In any case, Daniel's answer is definitive.
Dependendy Walker shows all deps of your program.
The correct answer to this question, in my view, is to start at the source rather than to reverse engineer the solution with Dependency Walker, awesome and useful tool though it undoubtedly is.
The problem with Dependency Walker is that it only tells you what one particular run of the program requires on the OS on which you run it. If you have any dynamic loading dependencies in your app then you would only pick those up if you made sure you profiled the app with Dep. Walker and forced it through those dynamic loads.
My preferred approach to this problem is to start with your own source code and analyse and understand what it depends upon. It's often easy enough to do so because you know it well.
You need to understand what are the deployment requirements for your compiler. You usually have options of linking statically and dynamically to the C++ runtime. Obviously a dynamic link results in a deployment requirement.
You will also likely link to 3rd party code. One example would be Windows components. These typically don't need deployment, you can take them as already being in place. Sometimes that's not true, e.g. GDI+ on Windows 2000.
Sometimes you will link statically to 3rd party code (again easy), but if you link dynamically then that implies a deployment requirement.
I built a VB Windows Forms application a while back using VS05 (or VS08? Not exactly sure) that I've recently converted to use VS10. I reference a .dll called ExcelPackage (another article, usage) so that I can create/manipulate Excel docs serverside. This app has worked fine on my old computer (PC/Vista) for a number of years. However, I have tried to move it to my new computer (PC/Win7 64-bit), and I can't get it to recognize the ExcelPackage .dll.
I have tried recompiling the .dll in VS10 and dropping the new .dll in my bin folder and re-referencing it. When I do this, before I try building, all my errors go away and I am actually able to navigate the class using VS10's built in ability (mouse over Imports OfficeOpenXml and you get a dropdown arrow that allows you to go through the classes). After I build, I get a green squiggly under my Imports OfficeOpenXml statement (can't find the reference).
I did some research and discovered that the .dll containing System.IO.Packaging has been moved around in .NET 3.0 and even re-referenced the new .dll, rebuilt, re-added, re-referenced, still no dice.
Am I missing something, or how do I get my application to recognize this assembly so that I can compile and continue working?
Thanks.
I don't see anything special about that project. Do note that the solution and project need to be converted. When that happens, you'll end up targeting the .NET 2.0 framework. That won't work out well, it has an assembly reference to WindowsBase, a 3.0 assembly. Make sure you update the target.
We have recently decided to start shipping the versions of some of the DLL files that a product requires with the product itself.
This is to guard against the situation where (for example) the MVC DLL file is updated on the server to which the software is deployed and the product fails to work as it was written against the now previous version of the DLL.
If the MVC DLL file of the specific version is included in the product and "locally" referenced this prevents this problem from happening. (In an ideal world every product which will be installed onto the destination server would be updated to the most recent version but this is not always practical)
My concern and question is whether this is going to give a false sense of security or not actually cope with the problem in the following situation: if Version 1.0 of the MVC DLL file is relying on method X of standard Microsoft DLL library Y and this DLL file Y is updated we will be in the same situation of having a broken product?
Assuming you meant the MSVC (Microsoft Visual C++) DLLs, the correct solution is to use an application manifest. The MSVC DLLs support Side by Side installation (SxS). This means that a new version of those DLLs does not replace an old version. Your application manifest tells Windows which DLL version(s) you want.
I don't know about MVC specifically, but you have a bigger problem if the conflicting version of a dependency dll is installed to the GAC on your target machine, as it will be used in preference to the local file.
Depending on how big it would make your final product, consider statically linking your program. This will prevent the much dreaded DLL hell since you wont have to give DLLs out.