It is good to have some faults tolerance in software instead of exit abruptly :)
> On 8 Nov 2021, at 6:44 PM, Gyan Doshi <ffm...@gyani.pro> wrote: > > > >> On 2021-11-07 02:56 pm, Marton Balint wrote: >> >> >>> On Sun, 7 Nov 2021, Gyan Doshi wrote: >>> >>> >>> >>> On 2021-11-07 03:58 am, Anatoly wrote: >>>> On Thu, 4 Nov 2021 20:14:16 +0800 >>>> LianCheng <tanl...@gmail.com> wrote: >>>> >>>>> Yes, would like to know in ffmpeg, under drawtext, the textfile >>>>> (reload=1) is using read-write or read-only mode? >>>> I think "procmon.exe" from Microsoft >>>> https://docs.microsoft.com/en-us/sysinternals/downloads/procmon >>>> can help you to find the answer (and maybe somehow "debug" the >>>> situation). >>> >>> FFmpeg opens the file with O_RDONLY mode. >>> >>>> Btw, I think following approach may help (or may not, I have no windows >>>> system by hand to test it myself). Let's say I want to atomically >>>> replace file a.txt with file b.txt >>>> mklink /h wrk.txt a.txt >>>> open wrk.txt with ffmpeg >>>> update b.txt as needed >>>> mklink /h next.txt b.txt >>>> move /y next.txt wrk.txt >>>> now update a.txt as needed or may delete a, b and create new b. >>>> hardlink again and move again >>>> and so on in loop >>> >>> This can work until it doesn't. The filter doesn't tolerate any load >>> failures. >>> I'll see if I can add a short sleep and retry. If it still fails, we >>> continue with the old text. >> >> I am not a fan of this to be honest. There is a proper way to do atomic >> renames even in windows, see the referenced stackoverflow articles, so it >> should just work. > > The comments at SO by Craig Barkhouse ('NTFS developer at Microsoft') says > that "ReplaceFile is most definitely NOT atomic." and that, forMoveFileEx, > atomicity is not guaranteed, depending on the underlying fs ops the call > leads to. So, I think some fault tolerance on our part is called for. > > Instead of a sleep and retry, we can simply continue with existing text and > try again on next frame. We can also extend the semantics of the option (in a > backward-compatible way) to specify the frame interval at which the file is > reloaded. > > Regards, > Gyan > _______________________________________________ > ffmpeg-user mailing list > ffmpeg-user@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-user > > To unsubscribe, visit link above, or email > ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe". _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
