Re: [boost] [Boost.Threads] New Feature: thread function parameter

From: Anthony Williams (anthony_w.geo_at_[hidden])
Date: 2007-02-08 10:03:34

Eugene Lyubimkin <yf_at_[hidden]> writes:

> I want to propose a new feature in *Boost.Threads
>
> *Now class _boost::thread_ have only one constructor:
> /thread::thread( const function0<void>& )
>
> /So we cannot send any parameter to thread's main function, because its 
> prototype have no parameters.
> My proposal: let add constructor
> /thread::thread( const function1<void, void*>& )/
> Parameter with type /void* /will be sent to thread function.
>
> Currently *Boost.Threads *supports Win32 API and POSIX API.
> Both these APIs support sending one parameter /void*/ to thread's main 
> function.

You're right that the underlying APIs support sending a single parameter to
the thread function, and you're also right that the thread constructor only
takes a function<void>. However, this is not as limiting as it appears. The
parameter is a function object, not a function pointer, so you can create your
functor any way you like. For example, you can use boost::bind to pass
parameters to a normal function:

void some_func(int i);

boost::thread some_thread(boost::bind(some_func,42)); // thread runs some_func(42)

Anthony
-- 
Anthony Williams
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