ffurl_open        611 libavformat/async.c     ret = ffurl_open(&h, "async:async-test:", AVIO_FLAG_READ, NULL, NULL);
ffurl_open        687 libavformat/async.c     ret = ffurl_open(&h, "async:async-test:", AVIO_FLAG_READ, NULL, &opts);
ffurl_open        151 libavformat/url.h int ffurl_open(URLContext **puc, const char *filename, int flags,