Re: [Boost-users] boost.asio async_write/read_until guarantee

From: dizzy (dizzy_at_[hidden])
Date: 2008-08-20 04:09:54

On Tuesday 19 August 2008 18:45:39 Daniel Mierswa wrote:
> Hi,
Hello

> if i have a threadpool running an io_service and a read_until is invoked
> before async_write. Now i wonder what would happen if the string is
> written to the socket, will the write handler be called before the
> read_handler or is it undefined in which order they will be invoked?

Unspecified order because it largely depends on:
- OS specifics like TCP input/output buffer sizes and message size sent/read
- asio implementation details

> If
> it's not guaranteed can anyone think of a solution to create such a
> guarantee in my own program? 

But once your read handler is called there is no more read operation on the 
socket until you do another async_read in the handler (or other code). So no 
read handler will be called. Just do an async_write in the read handler 
without any async_read, wait for the write handler to be called and there you 
use async_read to manifest interest in reading again. Thus no read handler 
will be called until the write handler is called where you do the async_read.

-- 
Dizzy
			"Linux is obsolete" -- AST