Module Atomic

module Atomic: sig .. end

Atomic references.

See 'Memory model: The hard bits' chapter in the manual.

Since 4.12

type 'a t

An atomic (mutable) reference to a value of type 'a.

val make : 'a -> 'a t

Create an atomic reference.

val get : 'a t -> 'a

Get the current value of the atomic reference.

val set : 'a t -> 'a -> unit

Set a new value for the atomic reference.

val exchange : 'a t -> 'a -> 'a

Set a new value for the atomic reference, and return the current value.

val compare_and_set : 'a t -> 'a -> 'a -> bool

compare_and_set r seen v sets the new value of r to v only if its current value is physically equal to seen -- the comparison and the set occur atomically. Returns true if the comparison succeeded (so the set happened) and false otherwise.

val fetch_and_add : int t -> int -> int

fetch_and_add r n atomically increments the value of r by n, and returns the current value (before the increment).

val incr : int t -> unit

incr r atomically increments the value of r by 1.

val decr : int t -> unit

decr r atomically decrements the value of r by 1.