Working with DLL in a C++ application

Question

I'm planning to use id3lib in my application. I'm looking for a way to use the library as a DLL. I've noticed that they released the library in various form: one of which is windows binary. My target platform in Windows, and I'll use Qt 4.8. After I extract the files in windows binary, I found the following files in Release folder:

• id3lib.dll
• id3lib.exp
• id3lib.lib

I know how to use a DLL in Qt given the DLL, one or more header files where function prototypes resides, and with or without the *.lib file. This package doesn't come with a header file.

How am I supposed to use this package without any header file? What's the purpose of the *.lib and *.exp files here? As far as I know *.lib files are used for static linking with functions which I don't want in my program.

Answer 1

The usual course is to use a header file #included in the C++ file, the .lib file to link to and the .dll is required at run time.

The header file should/may be in another package as the same header is probably used for different kinds of linking strategies.

At worst you should be able to use a tool such as depends.exe to view the exported symbols and create your own h file to match - but it would be better to find a .h file issued with the release.

Answer 2

You've just missed the header. It is available under the include subfolder (see here), also the .lib file is still needed for linking, even if you'll be using the DLL.