Syslinux - May 2010 - Why does the extlinux installer rewrite the first sector of extlinux.sys?

Hi,

I don't get the point of the write-patch-rewrite sequence.  Why is it
done this way?  I mean, why patch the first sector if you rewrite it
anyway?  Or why rewrite it, if you don't patch it?  (I didn't check
whether patch_file_and_bootblock touches the first sector or not.)
-- 
Thanks,
Feri.

On 05/30/2010 02:17 AM, Ferenc Wagner wrote:
> Hi,
> 
> I don't get the point of the write-patch-rewrite sequence.  Why is it
> done this way?  I mean, why patch the first sector if you rewrite it
> anyway?  Or why rewrite it, if you don't patch it?  (I didn't check
> whether patch_file_and_bootblock touches the first sector or not.)
It needs to know where on the disk it will be allocated blocks by the
filesystem.  The patching is putting in pointers to the file itself into
the file.

	-hpa
-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.