Subject: Re: direct copy() between two proc address spaces
To: None <tech-kern@netbsd.org>
From: Ian Zagorskih <ianzag@megasignal.com>
List: tech-kern
Date: 06/21/2004 17:25:11
On Monday 21 June 2004 07:33, der Mouse wrote:
> >
> > If i understand your idea correctly, isn't this kind of functionality
> > should be available using POSIX named shared memory ?
>
> I don't know.  Where can I find a description of this facility?

Take a look at shm_open() at 
http://www.opengroup.org/onlinepubs/009695399/functions/shm_open.html

> I suspect, though, that it is not, because all of the shared memory
> interfaces I have seen demand that the memory be created as shared
> memory - it is not possible, using them, to take memory allocated by
> some other means (data segment, malloc(), etc) and share it, which it
> is with what I am suggesting.

I guess i understand now: application allocates memory region from private 
address space and next shares it some way with other process. I also cannot 
recall anything with this functionality. Well, on the other hand, what's the 
advantage of this scheme ?

// wbr