Module CCSemaphore

Semaphores

Since: 0.13

type t

A semaphore

val create : int ‑> t

create n creates a semaphore with initial value n.

Raises Invalid_argument: if n <= 0.

val get : t ‑> int

Current value.

val acquire : int ‑> t ‑> unit

acquire n s blocks until get s >= n, then atomically sets s := !s - n.

val release : int ‑> t ‑> unit

release n s atomically sets s := !s + n.

val with_acquire : n:int ‑> t ‑> f:(unit ‑> 'a) ‑> 'a

with_acquire ~n s ~f first acquires s with n units, calls f (), and then releases s with n units. Safely release the semaphore even if f () fails.

val wait_until_at_least : n:int ‑> t ‑> f:(unit ‑> 'a) ‑> 'a

wait_until_at_least ~n s ~f waits until get s >= n, then calls f () and returns its result. Doesn't modify the semaphore.