Re: [Qemu-devel] [RFC PATCH 1/4] qemu-options: Add -filefd command line option

[Kevin Wolf <kwolf@redhat.com>]

Am 22.05.2012 15:25, schrieb Corey Bryant:
> 
> 
> On 05/21/2012 05:40 PM, Eric Blake wrote:
>> On 05/21/2012 02:19 PM, Corey Bryant wrote:
>>> This patch provides support for the -filefd command line option.
>>> This option will allow passing of a filename and its corresponding
>>> file descriptor to QEMU at exec time.
>>>
>>> Signed-off-by: Corey Bryant<coreyb@linux.vnet.ibm.com>
>>
>>> +DEF("filefd", HAS_ARG, QEMU_OPTION_filefd,
>>> +    "-filefd file=<filename>,fd=<fd>\n"
>>
>> I take it that if filename contains ',', then we have to escape it on
>> the command line?  Is it worth passing fd first and file second by
>> default, as a possible way to avoid the need for escaping, or does the
>> option parser not care about ordering?
>>
> 
> That's a good question.  The options can be ordered either way so I 
> don't think we'll force fd to be specified first.  I imagine this should 
> behave no differently than "-drive file=xyz,if=none,...".  I ran a quick 
> test using -drive with a filename that had a comma, and (escaped or not) 
> it failed on the option parsing.  So it looks like if you have a path 
> with a comma you're not going to have any luck.

I think you can escape it, you'd have to use a double comma. But I'd
rather not introduce more of this. It's another good reason for using
/dev/fd/... instead of a translation table.

Kevin