#compdef ulimit

[[ $PREFIX = u* ]] && compadd unlimited && return 0

local -a opts
setopt localoptions extendedglob

opts=(
  ${${${(fo)"$(ulimit -a)"}:#-N*}%%  *}
)
_arguments -s \
  '-H[set hard limits]' \
  '-S[set soft and hard limits (with -H)]' \
  '-N+[specify limit by number]:limit number' \
  "(-N ${(M@j: :)opts#-?} *)-a[list all current resource limits]" \
  ${opts/(#b)(-?): (*)/$match[1][$match[2]]:$match[2]} \
  '*:file size (blocks)'