NAME

Condition - Condition variables to synchronize between threads.

Module

Module Condition

Documentation

Module Condition
: sig end
 
 
Condition variables to synchronize between threads.
 
Condition variables are used when one thread wants to wait until another thread has finished doing something: the former thread 'waits' on the condition variable, the latter thread 'signals' the condition when it is done. Condition variables should always be protected by a mutex. The typical use is (if D is a shared data structure, m its mutex, and c is a condition variable): 
 

     Mutex.lock m;

 

     while (* some predicate P over D is not satisfied *) do

 

       Condition.wait c m

 

     done;

 

     (* Modify D *)

 

     if (* the predicate P over D is now satisfied *) then Condition.signal c;

 

     Mutex.unlock m

 
 
 
 
 
 
type t
 
 
The type of condition variables.
 
 
 
val create : unit -> t
 
Return a new condition variable.
 
 
 
val wait : t -> Mutex.t -> unit
 
 
wait c m atomically unlocks the mutex m and suspends the calling process on the condition variable c . The process will restart after the condition variable c has been signalled. The mutex m is locked again before wait returns.
 
 
 
val signal : t -> unit
 
 
signal c restarts one of the processes waiting on the condition variable c .
 
 
 
val broadcast : t -> unit
 
 
broadcast c restarts all processes waiting on the condition variable c .