Visual Studio Static Library Linker Settings
Laverne Levenstein
I am trying to add static libraries to my project. To add the static library I am following Microsoft's instructions: -us/library/ms235627.aspx.My problem is I that am not able to see the dependent library while adding the reference to my project.
The tutorial you have provided refers to a case in which you create your own static library - in this case you may want to add it to your solution and thus make it an integral part of the solution; but I assume you are trying to add external libraries (not created by you, e.g. downloaded from the net) - that is why you got stuck.
Revealing my ignorance: Why doesn't a static library project (in Visual Studio in my case) have linker settings in the project properties page? I thought "linking" was kind of a big deal re: libraries, but apparently I fundamentally misunderstand something.
Linking is the act of pulling together all your object files and libraries to create an executable. In a static library project you're not making an executable, you're just creating a library which will later be linked.
For example (and this is UNIX rather than Windows, but the concepts are similar), you would use the compiler cc to turn your source files into object files and the archiver ar to turn those into a library. The linker (or linkage editor) ld does not need to take part until you wanted to go to the next step and include your library into an executable.
My question is: is there an easier way to design API Wrapper Lib so that it embeds static.lib within itself, or automatically tells the linker "hey, when folks link against my .lib, make sure you also look to "static.lib" to resolve any missing symbols"
I could also have simply spelled out the exact location of this file as an absolute path. That removes my need to standardize what client projects relationship will be to this wrapper API library which "injects" the static library, but introduces the need for an absolute path meaning this wrapper library cannot move.
When you build on the Visual Studio command line, you must build the program in two steps. First, run cl /c /EHsc MathLibrary.cpp to compile the code and create an object file that's named MathLibrary.obj. (The cl command invokes the compiler, Cl.exe, and the /c option specifies compile without linking. For more information, see /c (Compile Without Linking).) Second, run lib MathLibrary.obj to link the code and create the static library MathLibrary.lib. (The lib command invokes the Library Manager, Lib.exe. For more information, see LIB Reference.)
Before you can use the math routines in the static library, you must reference it. Open the shortcut menu for the MathClient project in Solution Explorer, and then choose Add > Reference.
I just generated a small example, where I was able to reconstruct the linker error. The whole project is much more complicated, and the most part (special the Cpp part) is written by another colleagues. I just wanted to use their static library in my Fortran code.
Your static library has a dependency on the cuda runtime API library - cudart. You need to explicitly link against cudart in your project settings. See here. The library that you want to add is cudart.lib It will also be necessary to add the path to cudart.lib to the linker library paths in your project settings. These steps are actually not unique to CUDA; the general method to add a library or library path to the link specification for a VS project is something you can google for.
Most Visual C++ learners learn these settings the hard way, by observing Visual C++ compiler and linker errors, identified by their error code. For example, one may look up LNK2005, with the superficial meaning of "The symbol symbol was defined more than once," but with the understanding that the duplicate definition does not arise from a careless programming mistake, instead it could have happened because of some conflicts or misapplications of compile and linking options.
To provide a more specific and useful answer to your situation, one will need to know the names of the libraries you intend to use, as well as the linking errors or other difficulties you encounter. You may find existing answers to those questions in the respective library's discussion boards. These questions tend to be tagged with "linking issues", "windows", and "visual C++".
I am using a Cypress CY7C68013A USB chip to develop some hardware that will connect to a PC. I want to use LabView to send and receive data via this interface. The driver provided by Cypress for this IC is accessed via a statically compiled MS Visual C++ library called CyAPI.lib. I do not have access to the source code. I do have documentation on the API. I suspect that I will have to write a C wrapper for each object field/method. I would like to avoid this if possible. What are my options for getting LabView to access the CyAPI.lib?
To quote Microsoft : "A static library is a file containing objects and their functions and data that is linked into your program when the executable file is built. This topic explains how to create the starter files and project settings for a static library. You can link a static library to an MFC-based program or to a non-MFC program for Windows written in C or C++, that makes calls to the Win32 API rather than to MFC classes. "
However when I try to run the resulting exe I get errors about missing .dll files. If I add these files to my project root the program runs fine, and as far as I understand it this problem comes about from me having linked to the dynamic library according to the SFML setup tutorial. This tutorial is made for visual studio though, and I'm not sure which flags to be setting and which options I should change in order to link to the static library which will build everything into the exe.
This tutorial will cover step-by-step how to compile and reference your libraries with plenty of visuals. This article is intended to be repetitive to help beginners grasp and develop their own libraries with Microsoft Visual C++. I strongly recommend you read my previous article about compiling libraries with MinGW. The article provides a comparison between static and dynamic libraries. In general, I find the GCC compiler easier to comprehend and easier to develop libraries. This will assist beginners in developing their own libraries.
The code for a static library is identical to that in my previous post on compiling libraries for MinGW, found here. This is an over simplistic library to emphasize the process of creation, not the concept of a library. The library is pretty standard, in that the function is declared in the header and defined within the 'c/cpp' file. The files are listed below:
The alternative to using the wizard is to use the project properties. The second option allows a user to implement a static library after following the Wizard. A "use case" for this might be where you intended to implement an application, but after that is decided, it would be best suited as a static library. To implement this change, go to Project->Add Properties->General and select Static Libraries from the configuration field (refer to figure above). To compile the solution, right click on the solution and hit Build.
The implementation of the library is pretty standard. You must have access to the header file and reference it. If you do not have the header file, or do not wish to reference it, you must indicate the function definition with the extern tag. The main.c file is pretty standard, and demonstrates how to run a static library. You'll notice in the next figure that a new project was added to the library solution file. To add a new project to a solution, right-click on the solution file and hit Add New Project.
To implement this method, include the project you want into the current solution. (In the case of this example, you should have already added a new project to the library solution). If not, you will need to right-click on the Solution File->Add->Existing Project. Now right-click on the project that will depend upon your static library: select Common Properties->Framework and Reference->Add New Reference and select the project that has the required dependencies. If you have completed this successfully, you should see something similar to the image below.
In order to reference your newly compiled library (or a third party library), you can navigate to your "Debug" or "Release" directory to select your newly compiled library file. Grab the file labeled Add.lib or *.lib for any other library, and drag it over to your project resources. The drag and drop method is much simpler than the following method of using the configuration. You must also identify your library file so that the linker is able to properly identify the compiled function. To this, you must include your library header, or add an extern reference defining the functions you wish to call.
The tutorial for the dynamic library is intended to be as similar as possible to the static library. You'll notice that the only addition is __declspec(dllexport), which is a Microsoft specific identifier, which identifies that the function will be used as a DLL (Dynamically Linked Library) export. The C file is exactly the same as the previous examples.
The Wizard method to creating a dynamic library is very similar to the static library as mentioned above. I selected DLL from Application Type and selected Empty Project. If you do not select Empty Project, you will have to delete the files provided by the IDE. Although the project files provided by the Wizard have a specific purpose, they will over complicate this tutorial.
To implement this method, include the project you want into the current solution. (In the case of this example, you should have already added a new project to the library solution.) If not, you will need to right-click on Solution File->Add->Existing Project. Now right-click on the project that will depend upon your static library: select Common Properties->Framework and Reference->Add New Reference, and select the project that has the required dependencies. In the case of our library, you should only see one project to reference.
aa06259810