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http://www.linuxfromscratch.org/view/3.3/chapter05/kernel.html: |
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Why we copy the kernel headers and don't symlink them |
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In the past, it was common practice for people to symlink the |
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/usr/include/linux and asm directories to /usr/src/linux/include/linux and |
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asm respectively. This is a bad idea as this extract from a post by Linus |
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Torvalds to the Linux Kernel Mailing List points out: |
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I would suggest that people who compile new kernels should: |
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- not have a single symbolic link in sight (except the one that the |
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kernel build itself sets up, namely the "linux/include/asm" symlink |
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that is only used for the internal kernel compile itself) |
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And yes, this is what I do. My /usr/src/linux still has the old 2.2.13 |
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header files, even though I haven't run a 2.2.13 kernel in a _loong_ |
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time. But those headers were what glibc was compiled against, so those |
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headers are what matches the library object files. |
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And this is actually what has been the suggested environment for at |
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least the last five years. I don't know why the symlink business keeps |
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on living on, like a bad zombie. Pretty much every distribution still |
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has that broken symlink, and people still remember that the linux |
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sources should go into "/usr/src/linux" even though that hasn't been |
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true in a _loong_ time. |
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The relevant part here is where he states that the headers should be the |
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ones which glibc was compiled against. These are the headers which should |
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remain accessible and so by copying them, we ensure that we follow these |
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guidelines. Also note that as long as you don't have those symlinks, it is |
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perfectly fine to have the kernel sources in /usr/src/linux. |
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----- Original Message ----- |
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From: "Sean" <sean@××××××××××.org> |
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To: <wilbertml@×××××××××.net>; <gentoo-dev@g.o> |
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Sent: Sunday, September 08, 2002 7:14 AM |
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Subject: Re: [gentoo-dev] linux-headers-2.4.19 related to glibc-2.2.5? |
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-----BEGIN PGP SIGNED MESSAGE----- |
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Hash: SHA1 |
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It shouldn't cause any problems ... since I don't use the gentoo supplied |
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kernel source, I always keep a symlink from /usr/src/linux/include/linux to |
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/usr/include/linux |
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|
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Sean |
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