@@ -327,6 +327,8 @@ typedef struct AVIOContext {

      * This is current internal only, do not use from outside.

      */

     int (*short_seek_get)(void *opaque);

+

+    int64_t written;

 } AVIOContext;

 /**

@@ -120,6 +120,7 @@ int ffio_init_context(AVIOContext *s,

     s->current_type          = AVIO_DATA_MARKER_UNKNOWN;

     s->last_time             = AV_NOPTS_VALUE;

     s->short_seek_get        = NULL;

+    s->written               = 0;

     return 0;

 }

@@ -154,6 +155,9 @@ static void writeout(AVIOContext *s, const uint8_t *data, int len)

             ret = s->write_packet(s->opaque, (uint8_t *)data, len);

         if (ret < 0) {

             s->error = ret;

+        } else {

+            if (s->pos + len > s->written)

+                s->written = s->pos + len;

         }

     }

     if (s->current_type == AVIO_DATA_MARKER_SYNC_POINT ||

@@ -323,6 +327,9 @@ int64_t avio_size(AVIOContext *s)

     if (!s)

         return AVERROR(EINVAL);

+    if (s->written)

+        return s->written;

+

     if (!s->seek)

         return AVERROR(ENOSYS);

     size = s->seek(s->opaque, 0, AVSEEK_SIZE);

@@ -33,7 +33,7 @@

 // Also please add any ticket numbers that you believe might be affected here

 #define LIBAVFORMAT_VERSION_MAJOR  57

 #define LIBAVFORMAT_VERSION_MINOR  72

-#define LIBAVFORMAT_VERSION_MICRO 100

+#define LIBAVFORMAT_VERSION_MICRO 101

 #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \

                                                LIBAVFORMAT_VERSION_MINOR, \