#compdef comm

local -a args

args=(
  '-1[suppress lines unique to FILE1]'
  '-2[suppress lines unique to FILE2]'
  '-3[suppress lines that appear in both files]'
  '1:file1 to compare:_files'
  '2:file2 to compare:_files'
)

if _pick_variant gnu=GNU unix --version; then
  args+=(
    '(- : *)--version[display version information]'
    '(- : *)--help[display help information]'
  )
fi

_arguments -s $args