From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Petazzoni Date: Fri, 8 Mar 2013 09:50:41 +0100 Subject: [Buildroot] [RFD] IPv6 .... In-Reply-To: <51394B12.8090608@wp.pl> References: <51394B12.8090608@wp.pl> Message-ID: <20130308095041.7504bd0d@skate> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net Dear W.P., On Fri, 08 Mar 2013 03:21:06 +0100, W.P. wrote: > I am a bit ... with options in buildroot "require IPv6". > And what if USER does NOT want to enable / build IPv6? Some packages do require the C library to support IPv6, regardless of whether your network is using IPv6 or not. IPv6 support in the C library has added a number of specific data structures and defines, so if a given software package uses those IPv6-specific data structures and definitions unconditionally, then this package requires IPv6. For some packages, we have patches to make this code conditional on the presence of IPv6. But for some other packages, we believe it's not worth the effort because the package is huge and therefore adding IPv6 support in the C library is not a big deal in terms of binary size. > If he/she relies only on IPv4? No problem, you can have IPv6 support in your C library, and still use IPv4 only. It's just that your C library will be a little bit larger than necessary, but we're talking about a few dozens of KB, not more. > In "regular" Linux distributions (like mine, Fedora 16), there is NO > easy way to get rid of IPv6. Except deleting all ipv6 related stuff from > /lib/modules.... > > Why? > What for? Because they want to support IPv6, and supporting IPv6 is not as simple as installing an additional package: it requires support in the kernel, in the C library, and in all networking libraries and applications. Since they are binary distributions, they can generally only ship one configuration for each package, so they decide to ship it with IPv6. But really, what's the problem? What do you believe you will achieve by removing IPv6 support? > I know advantages of IPv6, but what "regular ISP" provides this? At least in France, there are several regular ISPs providing IPv6 support. There are also some private networks that use IPv6 internally. Best regards, Thomas -- Thomas Petazzoni, Free Electrons Kernel, drivers, real-time and embedded Linux development, consulting, training and support. http://free-electrons.com