[Libguestfs] [PATCH] supermin: Die with an error if no kernels found (RHBZ#539746).

[Richard W.M. Jones]

On Wed, Nov 25, 2009 at 09:25:37AM +0100, Jim Meyering wrote:
> First, on this kernels-assigning line,
> 
>     kernels=$(ls -1vr /boot/vmlinuz-*.$arch* 2>/dev/null | grep -v xen; ls -1vr /boot/vmlinuz-* 2>/dev/null | grep -v xen)
> 
> if you add ls' -d option, that will prevent a false-positive match
> if /boot/vmlinuz-* ever matches a directory containing something whose
> name includes "xen".
> 
> Also, you can avoid duplicating the "2>/dev/null | grep -v xen" part
> by using a single invocatin of ls, and then I noticed that the expansion
> of the second glob, /boot/vmlinuz-*, would include anything matched by
> the first one, so this is adequate:
> 
>     kernels=$(ls -1dvr /boot/vmlinuz-* 2>/dev/null | grep -v xen)

On rereading this, I understand the mistake.

The order that the kernels is presented in is significant, which is
why we first search for $arch-specific kernels, and secondly for
general kernels (in both cases avoiding Xen PV kernels).

However adding -d is an improvement.

Rich.

-- 
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