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From: Samuel Thibault <samuel.thibault@ens-lyon.org>
To: Jeff Garzik <jeff@garzik.org>
Cc: "Robert P. J. Day" <rpjday@crashcourse.ca>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: what's the purpose of MAXHOSTNAMELEN?
Date: Tue, 29 Dec 2009 20:56:08 +0100	[thread overview]
Message-ID: <20091229195608.GG4815@const> (raw)
In-Reply-To: <4B3A5B15.5060807@garzik.org>

Jeff Garzik, le Tue 29 Dec 2009 14:40:05 -0500, a écrit :
> On 12/29/2009 02:19 PM, Robert P. J. Day wrote:
> >arch/s390/include/asm/param.h:#define MAXHOSTNAMELEN	64	/* max 
> >length of hostname */
> >
> >   so lots of people define it but no one uses it.  it *is* exported to
> >user space in /usr/include/asm/param.h, but i still have no idea what
> >it's for in user space.  obsolete?
> 
> According to RFC 1034, "Each node has a label, which is zero to 63 
> octets in length"

That's for Internet networks.  Other kinds of networks could implement
more.  It could make sense to restrict ourself to Internet standards,
but we don't :)

> What is it used for in userspace, and why is it export from the kernel? 

Gethostname, typically, but also all kinds of functions that provide a
hostname.  It's also quite often completely badly used, for instance for
getnameinfo()...

You have Debian's list on
http://unstable.buildd.net/buildd/hurd-i386_Failed.html

Samuel

  reply	other threads:[~2009-12-29 19:56 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-12-29 19:19 what's the purpose of MAXHOSTNAMELEN? Robert P. J. Day
2009-12-29 19:28 ` Samuel Thibault
2009-12-29 19:40 ` Jeff Garzik
2009-12-29 19:56   ` Samuel Thibault [this message]
2009-12-29 20:20     ` Jeff Garzik
2009-12-29 20:26       ` Samuel Thibault
2009-12-29 21:00       ` Vikram Dhillon
2009-12-29 20:13   ` Robert P. J. Day

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