missing man page

No man page found for grep.1posix%20-E%20%27%5E%5Ba-zA-Z_-%5D%2B%3A.%2A%3F%23%23%20.%2A%24%24%27%20%24%28MAKEFILE_LIST%29%20%7C%20sort%20%7C%20awk%20%27BEGIN%20%7BFS%20%3D%20%22%3A.