Re: [Qemu-devel] [PATCH v2 1/1] doc: document chardev option 'append'

["Denis V. Lunev" <den@openvz.org>]

On 12/22/2015 01:26 PM, Daniel P. Berrange wrote:
> On Tue, Dec 22, 2015 at 12:49:09PM +0300, Denis V. Lunev wrote:
>>      commit 31e38a22a0c5a25646f966f001e1f5513d5a186d
>>      Author: Olga Krishtal <okrishtal@virtuozzo.com>
>>      Date:   Fri Dec 4 09:42:04 2015 +0300
>>
>>          qemu-char: append opt to stop truncation of serial file
>>
>> has added the option to the runtime but does not added it to -help
>> output. This blocks libvirt from using it.
> You can remove this sentance about libvirt - we stopped parsing
> -help output a long time ago. We exclusively use QMP now.
>
>> Signed-off-by: Denis V. Lunev <den@openvz.org>
>> CC: Dmitry Mishin <dim@virtuozzo.com>
>> CC: Eric Blake <eblake@redhat.com>
>> CC: Markus Armbruster <armbru@redhat.com>
>> CC: Paolo Bonzini <pbonzini@redhat.com>
>> ---
>> Changes from v1:
>> - fixed default value to 'off'
>>
>>   qemu-options.hx | 7 +++++--
>>   1 file changed, 5 insertions(+), 2 deletions(-)
>>
>> diff --git a/qemu-options.hx b/qemu-options.hx
>> index 49afe6c..f706e4a 100644
>> --- a/qemu-options.hx
>> +++ b/qemu-options.hx
>> @@ -2044,7 +2044,7 @@ DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
>>       "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
>>       "         [,mux=on|off]\n"
>>       "-chardev ringbuf,id=id[,size=size]\n"
>> -    "-chardev file,id=id,path=path[,mux=on|off]\n"
>> +    "-chardev file,id=id,path=path[,mux=on|off][,append=on|off]\n"
>>       "-chardev pipe,id=id,path=path[,mux=on|off]\n"
>>   #ifdef _WIN32
>>       "-chardev console,id=id[,mux=on|off]\n"
>> @@ -2199,7 +2199,7 @@ console with the given dimensions.
>>   Create a ring buffer with fixed size @option{size}.
>>   @var{size} must be a power of two, and defaults to @code{64K}).
>>   
>> -@item -chardev file ,id=@var{id} ,path=@var{path}
>> +@item -chardev file ,id=@var{id} ,path=@var{path} [,append=@var{on|off}]
>>   
>>   Log all traffic received from the guest to a file.
>>   
>> @@ -2207,6 +2207,9 @@ Log all traffic received from the guest to a file.
>>   created if it does not already exist, and overwritten if it does. @option{path}
>>   is required.
>>   
>> +@option{append} specifies that QEMU must truncate the file on open.
>> +@option{append} is optional, default value is off.
>> +
>>   @item -chardev pipe ,id=@var{id} ,path=@var{path}
>>   
>>   Create a two-way connection to the guest. The behaviour differs slightly between
> Assuming the commit msg is tweaked to remove mention of libvirt, then:
>
>    Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
>
> Regards,
> Daniel
No problem.

Thank you for your help to proceed with this in libvirt support of this
option :)

I'll resubmit this patch later after accumulating all feedback.

Den