Re: [Qemu-devel] [PATCH V3 3/7] qemu-nbd: add doc for internal snapshot export

[Wenchao Xia <xiawenc@linux.vnet.ibm.com>]

于 2013/10/1 22:49, Eric Blake 写道:
> On 09/25/2013 06:16 PM, Wenchao Xia wrote:
>> Signed-off-by: Wenchao Xia<xiawenc@linux.vnet.ibm.com>
>> ---
>>   qemu-nbd.c    |   11 ++++++++++-
>>   qemu-nbd.texi |   11 ++++++++++-
>>   2 files changed, 20 insertions(+), 2 deletions(-)
> This should be squashed into 2/7.  When adding new options, the
> documentation should be added at the same time.
>
   OK.

>> +"                       the temporary one\n"
>> +"  -l, --load-snapshot=SNAPSHOT_ID_OR_NAME\n"
>> +"                       load an internal snapshot inside FILE and export it\n"
>> +"                       as an read-only device\n"
>> +"  -L, --load-snapshot1=SNAPSHOT_PARAM\n"
>> +"                       load an internal snapshot inside FILE and export it\n"
>> +"                       as an read-only device, SNAPSHOT_PARAM format is\n"
>> +"                       'snapshot.id=[ID],snapshot.name=[NAME]'\n"
> Why can't ONE option be good enough?  In other words, make the command
> line parser smart enough so that:
>
> --load-snapshot=name
>
> tries SNAPSHOT_ID_OR_NAME, while
>
> --load-snapshot=snapshot.id=xyz,snapshot.name=name
>
> tries the SNAPSHOT_PARAM form.  In other words, if the optarg begins
> with 'snapshot.', assume the SNAPSHOT_PARAM form, otherwise use the
> SNAPSHOT_ID_OR_NAME form.  Then you only burn one short option letter,
> and avoid the problem with ambiguous abbreviation that I complained
> about in 2/7.
>
   I split the option as two item since want to keep capatiability for
"-s snapshot.id=xyz" in qemu-img convert, it is possible some one already
named a snapshot as "snapshot.id=xyz". But from the comments of Paolo, I 
think
add  a new option in qemu-img convert and deprecate -s, can solve the 
problem,
so I will use your format in next version, thanks for tipping that.