Import Upstream version 20180207

[hcoop/debian/mlton.git] / doc / guide / src / MLtonRlimit.adoc

MLtonRlimit
===========

[source,sml]
----
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`.