Your bug report

#9987: RFE: 'groups' command ADD command switches "-0", and "-1"

which was filed against the coreutils package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to 9987@debbugs.gnu.org.

-- 
9987: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=9987
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