[Libav-user] ffmpeg on android - cannot write output file

[wm4]

On Fri, 13 Feb 2015 17:52:58 +0100
Nicolas George <george at nsup.org> wrote:

> Le quintidi 25 pluviôse, an CCXXIII, Cen-bi Liu a écrit :
> > Thanks, that's a good point to see the error code. I will give it a try. I
> > just thought failure to open will result in a negative number. From the
> > list of error codes,
> > https://www.ffmpeg.org/doxygen/2.3/group__lavu__error.html, I don't see a
> > whole bunch related to different I/O errors, though.
> 
> FFmpeg uses the system error codes whenever possible. And you do not know it
> is a I/O-related error in the first place.

This is not quite true. FFmpeg error codes mangle system error codes in
some unintuitive way. See libavutil/error.h for details and macros that
convert between them. You probably want to use one of the functions to
convert the error to a string.