bug#55641: Using colours with grep

[Paul Eggert]

On 5/25/22 13:48, goncholden via Bug reports for GNU grep wrote:
> Have been using grep to colour the filename printed by tail using grep, by 
> setting GREP_COLOR.  However the setting does not work with GREP_COLORS.
>
> Additionally, I could not set colour values with tput commands.
>
> tail -v -n "$tm" $file | GREP_COLOR='01;32' $_GREP -e ^ -e '^==> .* <==$'

Sorry, I'm not following. Can you give a test case that I can reproduce 
here?