From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rick Jones <rick.jones2@hp.com>
Subject: Re: [NET]: Please revert disallowing zero listen queues
Date: Tue, 06 Mar 2007 10:54:00 -0800
Message-ID: <45EDB8C8.3030302@hp.com>
References: <200703061332.09677@strip-the-willow> <20070306.103706.68156515.davem@davemloft.net>
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	weid@np.css.fujitsu.com
To: David Miller <davem@davemloft.net>
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> So we're not "disallowing" a backlog argument of zero to
> listen().  We'll accept that just fine, the only thing that
> happens is that you'll get what you ask for, that being
> no connections :-)

I'm not sure where HP-UX inherited the 0 = 1 bit - perhaps from BSD, nor 
am I sure there is official chapter and verse, but:

<excerpt>
backlog is limited to the range of 0 to SOMAXCONN, which is 	defined in 
<sys/socket.h>.  SOMAXCONN is currently set to 4096.  If any other 
value is specified, the system automatically assigns the closest value 
     within the range.  A backlog of 0 specifies only 1 pending 
connection      is allowed at any given time.
</excerpt>

I don't have a Solaris, BSD or AIX manpage for listen handy to check 
them but would not be surprised to see they are similar.

rick jones