Re: [Qemu-devel] [PATCH][RFC] Add compare subcommand for qemu-img

[Paolo Bonzini]

Il 01/08/2012 15:21, Eric Blake ha scritto:
>> > +++ b/qemu-img.c
>> > @@ -96,7 +96,9 @@ static void help(void)
>> >             "  '-a' applies a snapshot (revert disk to saved state)\n"
>> >             "  '-c' creates a snapshot\n"
>> >             "  '-d' deletes a snapshot\n"
>> > -           "  '-l' lists all snapshots in the given image\n";
>> > +           "  '-l' lists all snapshots in the given image\n"
>> > +           "Parameters to compare subcommand:\n"
>> > +           "  '-g' Second image format (in case it differs from first 
>> > image)\n";
> As written, this sounds like:
> 
> No -f, no -g => probe both
> -f, no -g => -f applies to both
> no -f, -g => probe first, use -g for second
> -f, -g => use given formats for both
> 
> Is that really what you meant, or do we actually get:
> 
> -f, no -g => -f applies to first, probe second
> 
> I think both interpretations could make sense, but I'd prefer having the
> omission of -g imply probing the second file type regardless of the
> presence or absence of -f, for consistency.

+1

Paolo