getenv("HOME") returns "/root" with "sudo"

I'm writing a program on my Raspberry Pi that requires the function "getenv("HOME")" to locate "/home/pi".

However, since I'm using the "wiringPi" library that requires "sudo" to run, "getenv("HOME")" now returns "/root" as the HOME directory instead of "/home/pi".

Is there a way to locate "/home/pi" with "getenv("HOME")" while using "sudo" the run the program?

Any help will be appreciated. Thank you.