BUFSIZ is undefined #1
Description
BUFSIZ is undefined leading to error during compile. Normally BUFSIZ is defined by c compiler environment for standard IO and varies depending on environment.
from https://c-programming-know-how.blogspot.com/2014/03/what-is-bufsiz.html
"BUFSIZ is a constant macro representing the size of the input buffer. It is defined in stdio.h and represents the size for your C implementation. ANSI C requires that it be at least 256 bytes."