Re: [Boost-users] Newbie question-- how do I get a Lockable?

From: Bill Somerville (bill_at_[hidden])
Date: 2008-04-24 19:02:44

Hi Henry,

Henry Holmes wrote:
> Sorry if this is a dumb question-- it looks like just about every kind 
> of lock/mutex I could declare in the documentation wants to be passed 
> a Lockable object, but I can find no such thing in any of the header 
> files. I have the Boost Thread library installed and am able to make 
> and run threads, and I have all sorts of other lock and mutex stuff 
> defined, it just does not seem to correspond to the documentation at 
> all. Am I just horribly confused about what the documentation means? 
> Any help is greatly appreciated.
Lockable is not a type, it is a concept. Concepts are requirements a 
type must comply with to be used by a type or function. The Lockable 
concept is defined here 
http://www.boost.org/doc/libs/1_35_0/doc/html/thread/synchronization.html#thread.synchronization.mutex_concepts 
. The boost thread library provides types that implement these concepts 
and they may be substitued where a suitable concept is required. This is 
a form of polymorphism you may not be aware of. The types you may want 
to instantiate for your requirements are probably described here 
http://www.boost.org/doc/libs/1_35_0/doc/html/thread/synchronization.html#thread.synchronization.mutex_types 
note that they all implement at least the Locakble concept.

HTH

-- 
Bill Somerville
Class Design Limited