Write a c programming language code for 1,2,3, and implenment it and also write comments with with each step of c code and output also be shown

Implement "Cat" utility. 1. Cat a. Src: STDIN_FILENO b. Dest: STDOUT_FILENO 2. Cat file1.txt a. Src: file1.txt b. Dest: STDOUT_FILENO 3. Cat f1.txt > f2.txt a. Src: f1.txt b. Dest: f2.txt