bug#41700: grep -v always exiting with 1 for empty file

[Paul Eggert]

On 6/4/20 7:06 AM, Andi Kleen wrote:
> I would argue that a empty file has a single empty line.

No, an empty file has no lines. A single empty line would be a file of size 1,
containing just a newline byte.

> Besides it completely breaks the "is foo not in file" functionality.

That's not what -v is for. -v asks "is not-FOO in file". If you want "is FOO not
in file", use -L.