Re: [boost] [thread] countdown_latch

Subject: Re: [boost] [thread] countdown_latch
From: Michael Marcin (mike.marcin_at_[hidden])
Date: 2013-04-21 07:18:32

On 4/21/2013 5:45 AM, Vicente J. Botet Escriba wrote:
> Le 21/04/13 10:27, Michael Marcin a écrit :
>> I recently ran across the need to spawn a thread and wait for it to
>> finish its setup before continuing.
>>
>> The accepted answer seems to be using a mutex and condition variable
>> to achieve this.
>>
>> However that work clutters up the code quite a bit with the
>> implementation details.
>>
>> I came across Java's CountDownLatch which does basically the same work
>> but bundles it up into a tidy package.
>>
>>
> What about using boost::barrier [1]?
>
> Best,
> Vicente
>

Ah didn't know that existed. Looks like it serves a similar purpose.

Still there are a few differences.

Looks like barrier is a bit fatter to let it handle restarting on a new 
generation.

Usage requires you to know the number of people that are going to call 
wait at construction time as well.

IF you replaced the countdown_latch with barrier in my example you 
introduce more synchronization than is necessary.
In addition to the constructor waiting on thread_func now thread_func 
must wait for the constructor.