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From: Wes Peters <wes@softweyr.com>
Organization: Softweyr.com
To: Lev Walkin <vlm@netli.com>,
	zera holladay <zera_holladay@yahoo.com>
Date: Fri, 5 Sep 2003 11:47:39 -0700
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cc: hackers@freebsd.org
Subject: Re: Shared memory question
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On Friday 29 August 2003 20:31, Lev Walkin wrote:
> zera holladay wrote:
> > When one uses the term "shared memory" while
> > discussing Unix, then what is generally the meaning of
> > that term?  I have read that some Unixes have "shared
> > memory" for "shared objects."
> > [...]
>
> Shared memory is just a chunk of memory which may be
> created by one program and attached to (by) many other programs.
> Yes, the management (allocation and deallocation) of shared
> memory chunks are done in kernel. User space applications
> have to use shmget(2), shmat(2), shmdt(2) system calls
> to obtain, attach and release the chunk of shared memory.

Or mmap(2) with the MAP_SHARED attribute set.


-- 
         "Where am I, and what am I doing in this handbasket?"

Wes Peters                                              wes@softweyr.com