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Message-ID: <4C61F3FF.1080303@2ndquadrant.com>
Date: Tue, 10 Aug 2010 20:51:11 -0400
From: Greg Smith <greg@2ndquadrant.com>
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To: Tom Lane <tgl@sss.pgh.pa.us>
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Subject: Re: The function of lock file named ".s.PGSQL.<port>.lock" on Linux?
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Tom Lane wrote:
> We can't portably lock the socket file itself, so we make a separate
> ordinary file for locking purposes.
>   

It looks to me like the fact that the .lock file is created is only 
documented in src/backend/utils/init/miscinit.c , and even there the 
reason why (what you wrote above) isn't mentioned.  Seems like noting 
this file is created in the unix_socket_directory entry of the docs, and 
the rationale for why in the source code, would make a useful 
improvement.  Anybody want to write a little documentation patch?

-- 
Greg Smith  2ndQuadrant US  Baltimore, MD
PostgreSQL Training, Services and Support
greg@2ndQuadrant.com   www.2ndQuadrant.us