#compdef sleep

local sum inf fraction
local -a expl units

case $OSTYPE in
  linux-gnu)
    args=(
      -S
      '--help[display help information]'
      '--version[display version information]'
    )
  ;& # fall-through
  solaris*)
    inf="_phony infinity --"
  ;& # fall-through
  darwin*|freebsd*)
    units=( :s:seconds m:minutes h:hours d:days )
    sum='*'
    fraction='-f'
  ;;
esac

_arguments $args \
  "${sum}:interval:$inf _numbers $fraction -u seconds interval $units"