1Stdlib.Domain(3)                 OCaml library                Stdlib.Domain(3)
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NAME

6       Stdlib.Domain - no description
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Module

9       Module   Stdlib.Domain
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Documentation

12       Module Domain
13        : (module Stdlib__Domain)
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16       Alert  unstable.   The Domain interface may change in incompatible ways
17       in the future.
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25       Domains.
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27       See 'Parallel programming' chapter in the manual.
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29       type 'a t
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32       A domain of type 'a t runs independently, eventually producing a result
33       of type 'a, or an exception
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37       val spawn : (unit -> 'a) -> 'a t
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40       spawn f creates a new domain that runs in parallel with the current do‐
41       main.
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45       val join : 'a t -> 'a
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48       join d blocks until domain d runs to completion.  If  d  results  in  a
49       value, then that is returned by join d . If d raises an uncaught excep‐
50       tion, then that is re-raised by join d .
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53       type id = private int
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56       Domains have unique integer identifiers
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60       val get_id : 'a t -> id
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63       get_id d returns the identifier of the domain d
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68       val self : unit -> id
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71       self () is the identifier of the currently running domain
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75       val before_first_spawn : (unit -> unit) -> unit
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78       before_first_spawn f registers f to be called before the  first  domain
79       is   spawned   by  the  program.  The  functions  registered  with  be‐
80       fore_first_spawn are called on the main (initial) domain. The functions
81       registered  with before_first_spawn are called in 'first in, first out'
82       order: the oldest function  added  with  before_first_spawn  is  called
83       first.
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86       Raises Invalid_argument if the program has already spawned a domain.
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90       val at_exit : (unit -> unit) -> unit
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93       at_exit  f registers f to be called when the current domain exits. Note
94       that at_exit callbacks are domain-local and only apply to  the  calling
95       domain. The registered functions are called in 'last in, first out' or‐
96       der: the function most recently added with at_exit is called first.  An
97       example:
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100       let temp_file_key = Domain.DLS.new_key (fun _ ->
101         let tmp = snd (Filename.open_temp_file "" "") in
102         Domain.at_exit (fun () -> close_out_noerr tmp);
103         tmp)
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106       The  snippet above creates a key that when retrieved for the first time
107       will open a temporary file and register an at_exit  callback  to  close
108       it,  thus guaranteeing the descriptor is not leaked in case the current
109       domain exits.
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113       val cpu_relax : unit -> unit
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115       If busy-waiting, calling cpu_relax () between iterations  will  improve
116       performance on some CPU architectures
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120       val is_main_domain : unit -> bool
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123       is_main_domain () returns true if called from the initial domain.
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127       val recommended_domain_count : unit -> int
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129       The  recommended  maximum number of domains which should be running si‐
130       multaneously (including domains already running).
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132       The value returned is at least 1 .
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135       module DLS : sig end
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143OCamldoc                          2023-07-20                  Stdlib.Domain(3)