#compdef tty gtty

local -a args

if _pick_variant gnu='Free Soft' unix --version; then
  args=(
    '(-)--help[display help information]'
    '(-)--version[display version information]'
    '(-s --quiet --silent)'{-s,--quiet,--silent}'[suppress normal output]'
  )
else
  args=( '-s[suppress normal output]' )
  [[ $OSTYPE == solaris* ]] && args+=(
    "-l[display terminal's synchronous line number]"
  )
fi

_arguments -s -S : $args