[FFmpeg-devel] [PATCH] ffmpeg: block output == input for files

[Marton Balint]

On Thu, 30 Aug 2018, Paul B Mahol wrote:

> On 8/30/18, Gyan Doshi <gyandoshi at gmail.com> wrote:
>> On 29-08-2018 09:48 AM, Gyan Doshi wrote:
>>> On 29-08-2018 02:43 AM, Michael Niedermayer wrote:
>>>> On Tue, Aug 28, 2018 at 08:31:51AM +0200, Marton Balint wrote:
>>>
>>>>>
>>>>> Instead of this, maybe we should add support to write lock the files
>>>>> when
>>>>> opening them for reading. Then ffmpeg can request this. That would be an
>>>>> useful option, and not just for unexperienced users.
>>>>
>>>> depending on how this is done, it could interfere with reading a file
>>>> while
>>>> it is being written/appeneded to by another process
>>>
>>> Yes, a user may use a growing MPEG-TS file as input.
>>>
>>> Also, is there a universal & portable way to secure a write lock across
>>> all platforms?
>>>
>>> I think a 'soft' solution is preferable.
>>
>> Any suggestions or objections?
>>
>> If no, will push in a day.
>
> Please do not push, until consensus is reached.
>
> What about red log warning text?

Is there any real use case when same source and destination works, so the 
option can be used?

If not, then just make ffmpeg fail, like the cp command fails for same 
source and destination. I am against adding an option if it has no known 
use.

Thanks,
Marton