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Hi,</div>
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I have an open fd which has a specific file position (>0) and I provide that in the options dictionary for avio_open2. My assumption was that when writing with av_interleaved_write_frame it would start at the same position as the given fd has. But it always
starts at 0. Looking into the code for avio_open2 I can see that there is a seek set to 0 last in ffurl_connect. So I was wondering how this is supposed to work if you don't want to start at 0. Should I control the starting position with avio_skip after avio_open2
or is there a better way to do this? And would this work for different formats, i.e. matroska, mp4, cmaf? Or is there some reason that the file position must be 0?</div>
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Just some calls to illustrate:</div>
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avformat_alloc_output_context2(&oc, NULL, container_format, filename);</div>
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av_dict_set(&file_opts, "fd", "fd_no", 0);</div>
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avio_open2(&oc->pb, "fd:", AVIO_FLAG_READ | AVIO_FLAG_WRITE, NULL, &file_opts)</div>
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avio_skip(oc->pb, filepos) // would this work for e.g. mp4?</div>
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...then several...</div>
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av_interleaved_write_frame(oc, pkt)</div>
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...</div>
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Thanks!</div>
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Br, Kristina</div>
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