While I'm looking at the man page, a minor clarification. "All long options are provided" can be read to mean that every gnu option is provided. This is not intended, and a simple reordering makes things clearer imo.
Index: grep.1 =================================================================== RCS file: /cvs/src/usr.bin/grep/grep.1,v retrieving revision 1.49 diff -u -p -r1.49 grep.1 --- grep.1 7 Oct 2019 20:51:34 -0000 1.49 +++ grep.1 7 Oct 2019 20:53:26 -0000 @@ -364,7 +364,7 @@ are extensions to that specification, an .Fl f flag when used with an empty pattern file is left undefined. .Pp -All long options are provided for compatibility with +All provided long options are for compatibility with GNU versions of this utility. .Pp Historic versions of the
