Correctly importing an external library (Libltc)

Hello everyone, I am new to working with external libraries. I would like to include in my projects, some functions of the Libltc library (GitHub - x42/libltc: Linear/Logitudinal Time Code (LTC) Library) because I need to display on screen the SMPTE of a LTC that travels through an audio signal (If JUCE already has this function, I would appreciate if you could share it with me).
The problem is that this library is divided in .h and .c files and when I want to call a function, I get the error “unresolved external symbol”. I guess it is because it is not recognizing the .c file since I am only putting “#include <ltc.h>”.
Thank you very much in advance and sorry if this is a stupid question.

Are you using Projucer or Cmake? I believe Projucer has an ‘external libraries to link’ option. For Cmake, I think you could make a cmakelists in the libltc folder and use add submodule.

Thank you very much for your help. But when I compile it, it appears to be an .exp file but not a .lib file. Any idea how to proceed?

There are different approaches on how to integrate libraries in your project. Some third party libs come with clear instructions how to precompile it so that you generate that .lib or .a file on your own. For the library you linked, it contains a very simple automake makefile which is probably intended to build the library but no further instructions are given. Since the library does not seem too complex, you could just go and add all those .c files from the library to your project, so that they are compiled along with your code. I wouldn’t be surprised if that just worked in this case. But there are more complex libraries where an approach like that is not the usual way to go.