signature MLTON_RLIMIT =
   sig
      structure RLim : sig
                          type t
                          val castFromSysWord: SysWord.word -> t
                          val castToSysWord: t -> SysWord.word
                       end
      val infinity: RLim.t
      type t
      val coreFileSize: t        (* CORE    max core file size *)
      val cpuTime: t             (* CPU     CPU time in seconds *)
      val dataSize: t            (* DATA    max data size *)
      val fileSize: t            (* FSIZE   Maximum filesize *)
      val numFiles: t            (* NOFILE  max number of open files *)
      val lockedInMemorySize: t  (* MEMLOCK max locked address space *)
      val numProcesses: t        (* NPROC   max number of processes *)
      val residentSetSize: t     (* RSS     max resident set size *)
      val stackSize: t           (* STACK   max stack size *)
      val virtualMemorySize: t   (* AS      virtual memory limit *)
      val get: t -> {hard: rlim, soft: rlim}
      val set: t * {hard: rlim, soft: rlim} -> unit
   end
MLton.Rlimit provides a wrapper around the C getrlimit and setrlimit functions.
- 
type Rlim.t
the type of resource limits.
 - 
infinity
indicates that a resource is unlimited.
 - 
type t
the types of resources that can be inspected and modified.
 - 
get r
returns the current hard and soft limits for resource r. May raise OS.SysErr.
 - 
set (r, {hard, soft})
sets the hard and soft limits for resource r. May raise OS.SysErr.