Re: posix shared memory

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#49

From: YAMAMOTO Takashi
Date: Tue, 02 Apr 2013 02:27

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hi,

> Hi,
> 
> yamt@mwd.biglobe.ne.jp (YAMAMOTO Takashi) wrote:
>> i have userland implementation of posix shared memory.
>> (attached)
>> 
>> rmind proposed a kernel implementation while ago.
>> http://mail-index.netbsd.org/tech-kern/2009/07/30/msg005599.html
>> (thus cc:)
>> 
>> which way should we go?
>> 
>> IMO userland implementation is better because:
>> 	- simpler
>> 	- smaller
>> 	- a bug would have less impact
>> 	- "locking object in memory" functionality is better to be
>> 	  implemented with more generic api like fcntl if necessary
> 
> We should go with the userland implementation.  After some though I
> basically agree with you that facilities like memory locking can be
> implemented with fcntl, mount option tmpfs or whatever.
> 
> However, I would say it would be better to create tmpfs partition
> for this.  A while ago I came up with practically same code, but
> also checking for the fs type:
> 
> http://www.netbsd.org/~rmind/shm.c

i don't think it's a good idea to force fstype.
if we want to recommend tmpfs, it's a job for sysinst, not libc.

YAMAMOTO Takashi

> 
>> 
>> YAMAMOTO Takashi
> 
> -- 
> Mindaugas

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From: yamt@mwd.biglobe.ne.jp (YAMAMOTO Takashi)
Newsgroups: fa.netbsd.tech.kern
Subject: Re: posix shared memory
Date: Tue, 02 Apr 2013 02:27:49 UTC
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