Module Netplex_mutex

module Netplex_mutex: sig .. end

Netplex-wide mutexes

---

These are mutexes that work in both multi-processing and multi-threading netplex environments. They are implemented on top of Netplex_semaphore, and use the same name space for named objects.

For implementation issues, see Netplex_semaphore.

It is not required to create mutexes: A mutex is automatically created when the name is used for the first time. Mutexes are initially always in unlocked state.

Mutexes do not stack: A container cannot lock a mutex several times. (The second lock attempt would result in a deadlock.)

There is no deadlock detection.

If a container holding mutexes terminates the mutexes are automatically unlocked.

Mutex are not owned by their container. It is allowed that a different container unlocks the mutex.

Technically, a mutex named n is implemented by a semaphore n. If the mutex is locked, the semaphore has the value 0, and if it is unlocked, it has value 1.

Thread safety: Full. The functions can be called from any thread.

val plugin : Netplex_types.plugin

The following functions can only be invoked in container contexts. Outside of such a context the exception Netplex_cenv.Not_in_container_thread is raised.

type mutex 

val access : string -> mutex

val lock : mutex -> unit

val unlock : mutex -> unit

This web site is published by Informatikbüro Gerd Stolpmann