Adding RTC Library for Arduino Project in Visual Studio

Question

I am working in an Arduino project in visual studio. I need to get and set time to a RTC clock. That's why I am adding a ds3231 header file in my project from GitHub. When I want to build "it's showing me linking error.

cccSeqVu.ltrans0.o*: (.text.startup+0x1ea): undefined reference to DS3231_init(unsigned char)

My code is given below.

 #include <Wire.h>
 #include "ds3231.h"
 
 void setup(){
 Wire.begin();
 DS3231_init(0x4);
 }
 
 void loop(){
 }

Can anyone please help me to find out what I have missed.

• Juraj: add the whole library, not just the header file
• Iqbal Hossain: How to add the whole library in visual studio?
• Juraj: I don't know. I don't use platformio