Consider using _s variants of string functions

[sean-gilliam]

Since bare strcpy, sprintf, strcat, and their ilk are prone to security risks like buffer overflows and the like,
While we're updating the code, we should consider using the more secure _s variants of string functions (strcpy_s, sprintf_s, strcat_s, etc)

https://en.cppreference.com/w/c/string/byte/strcpy

https://docs.microsoft.com/en-us/cpp/c-runtime-library/reference/strcpy-s-wcscpy-s-mbscpy-s?view=vs-2019