package eio

  1. Overview
  2. Docs
Effect-based direct-style IO API for OCaml

Install 

dune-project
 Dependency

github.com Readme Changelog ISC License Edit opam file Versions (22)

Authors

  1. A
    Anil Madhavapeddy
  2. T
    Thomas Leonard

Maintainers

  1. A
    anil@recoil.org

Sources

eio-1.6.tbz
sha256=c1f04986b401094176494863dde1ca9b292b59fdc679a9d7023e558d80fb5b15
sha512=92ed8cf20300b8a4e0141bdbc373c0803c5a24530cb65852637d905fff4a5b956a8859a00a424034ff78c1112da9b0391194bcd558326168bdebd1ce683a8890

doc/eio/Eio/Semaphore/index.html

Module Eio.SemaphoreSource

A counting semaphore.

The API is based on OCaml's Semaphore.Counting.

The difference is that when waiting for the semaphore this will switch to the next runnable fiber, whereas the stdlib one will block the whole domain.

Semaphores are thread-safe and so can be shared between domains and used to synchronise between them.

Sourcetype t

The type of counting semaphores.

Sourceval make : int -> t

make n returns a new counting semaphore, with initial value n. The initial value n must be nonnegative.

Sourceval release : t -> unit

release t increments the value of semaphore t. If other fibers are waiting on t, the one that has been waiting the longest is resumed.

  • raises Sys_error

    if the value of the semaphore would overflow max_int

Sourceval acquire : t -> unit

acquire t blocks the calling fiber until the value of semaphore t is not zero, then atomically decrements the value of t and returns.

Sourceval get_value : t -> int

get_value t returns the current value of semaphore t.