Re: [Qemu-devel] [PATCH] qemu-io: Return non-zero exit code on failure

[Nir Soffer]

On Wed, Jan 11, 2017 at 11:51 PM, Eric Blake <address@hidden> wrote:
> On 01/11/2017 12:24 PM, Nir Soffer wrote:
>> From: Nir Soffer <address@hidden>
>>
>> The result of openfile was not checked, leading to failure deep in the
>> actual command with confusing error message, and exiting with exit code 0.
>>
>> Here is one example - trying to read a pattern from an invalid chain:
>>
>>     $ qemu-io -c 'read -P 1 0 1024' top.qcow2; echo $?
>
> As written, you have to guess some context about how top.qcow2 was
> created.  The example can be made a bit more reproducible with:
>
> $ : > file
> $ qemu-io -f qcow2 -c ... file

Right, I'll refine it in the next version.

>
>>     can't open device top.qcow2: Could not open backing file: Image is not 
>> in qcow2 format
>>     no file open, try 'help open'
>>     0
>>
>> With this patch, we fail earlier with exit code 1:
>>
>>     $ ./qemu-io -c 'read -P 1 0 1024' top.qcow2; echo $?
>>     can't open device top.qcow2: Could not open backing file: Image is not
>>     in qcow2 format
>>     1
>>
>> Signed-off-by: Nir Soffer <address@hidden>
>> ---
>>  qemu-io.c | 8 ++++++--
>>  1 file changed, 6 insertions(+), 2 deletions(-)
>
> Whether or not the commit message is improved,
> Reviewed-by: Eric Blake <address@hidden>
>
> --
> Eric Blake   eblake redhat com    +1-919-301-3266
> Libvirt virtualization library http://libvirt.org
>