Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751389AbZL2TkM (ORCPT ); Tue, 29 Dec 2009 14:40:12 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751340AbZL2TkL (ORCPT ); Tue, 29 Dec 2009 14:40:11 -0500 Received: from mail-gx0-f211.google.com ([209.85.217.211]:48489 "EHLO mail-gx0-f211.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751307AbZL2TkI (ORCPT ); Tue, 29 Dec 2009 14:40:08 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-type:content-transfer-encoding; b=QX5ufVV14kcW/Rf5rq0MTXlIDBHW6KXDSf2jRumo4qDTlGe4IjrXRQAj9MTak5tGdi QEciJFM2hxdT4AC2utV3TtLO5iYdKjtq9lhqk6daQCJ2z53E9J6c2Gn5no/2ZVSJXGje MBO3DXJ4czF+3j3nSyd5Oe9iZ2df9l7S/jRGU= Message-ID: <4B3A5B15.5060807@garzik.org> Date: Tue, 29 Dec 2009 14:40:05 -0500 From: Jeff Garzik User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.5) Gecko/20091209 Fedora/3.0-3.fc11 Thunderbird/3.0 MIME-Version: 1.0 To: "Robert P. J. Day" CC: Linux Kernel Mailing List Subject: Re: what's the purpose of MAXHOSTNAMELEN? References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2418 Lines: 46 On 12/29/2009 02:19 PM, Robert P. J. Day wrote: > > in prepping for coalescing a lot of param.h files, i'm curious about > the purpose of this macro: > > $ grep -rw MAXHOSTNAMELEN * > arch/s390/include/asm/param.h:#define MAXHOSTNAMELEN 64 /* max length of hostname */ > arch/sparc/include/asm/param.h:#define MAXHOSTNAMELEN 64 /* max length of hostname */ > arch/alpha/include/asm/param.h:#define MAXHOSTNAMELEN 64 /* max length of hostname */ > arch/mn10300/include/asm/param.h:#define MAXHOSTNAMELEN 64 /* max length of hostname */ > arch/arm/include/asm/param.h:#define MAXHOSTNAMELEN 64 > arch/m32r/include/asm/param.h:#define MAXHOSTNAMELEN 64 /* max length of hostname */ > arch/mips/include/asm/param.h:#define MAXHOSTNAMELEN 64 /* max length of hostname */ > arch/m68k/include/asm/param.h:#define MAXHOSTNAMELEN 64 /* max length of hostname */ > arch/xtensa/include/asm/param.h:#define MAXHOSTNAMELEN 64 /* max length of hostname */ > arch/ia64/include/asm/param.h:#define MAXHOSTNAMELEN 64 /* max length of hostname */ > arch/h8300/include/asm/param.h:#define MAXHOSTNAMELEN 64 /* max length of hostname */ > arch/avr32/include/asm/param.h:#define MAXHOSTNAMELEN 64 > arch/cris/include/asm/param.h:#define MAXHOSTNAMELEN 64 /* max length of hostname */ > arch/um/include/asm/param.h:#define MAXHOSTNAMELEN 64 /* max length of hostname */ > arch/powerpc/include/asm/param.h:#define MAXHOSTNAMELEN 64 /* max length of hostname */ > arch/parisc/include/asm/param.h:#define MAXHOSTNAMELEN 64 /* max length of hostname */ > arch/frv/include/asm/param.h:#define MAXHOSTNAMELEN 64 /* max length of hostname */ > include/asm-generic/param.h:#define MAXHOSTNAMELEN 64 /* max length of hostname */ > include/net/sctp/structs.h:#include /* We get MAXHOSTNAMELEN. */ > $ > > 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" What is it used for in userspace, and why is it export from the kernel? Good question... Jeff -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/