Re: [Boost-users] [asio] Why are the strands in the "HTTP Server 3" example necessary?

Subject: Re: [Boost-users] [asio] Why are the strands in the "HTTP Server 3" example necessary?
From: Boris Schaeling (boris_at_[hidden])
Date: 2010-01-07 16:11:24

On Thu, 07 Jan 2010 12:22:39 +0100, Tacheon <tacheon_at_[hidden]> wrote:

> In the  HTTP Server 3 (http://tinyurl.com/yh95d2b) example of the asio  
> documentation strands are used to synchronize the invocation of  
> completion handlers? But why are they necessary here? As far as I get  
> it, the handlers  are invoked in strict sequential order for each  
> distinct connection (http://tinyurl.com/ybohynd). Each connection has  
> its own set of resources so synchronization shouldn't be necessary,  
> should it?

I quickly checked the connection class and couldn't find a reason either  
why strand is used here. The comment in connection.hpp (///Strand to  
ensure the connection's handlers are not called concurrently) doesn't make  
any sense as a new asynchronous operation is only started when another  
ends. Maybe the strand is left over from an earlier version of the HTTP  
server?

Boris