1 files changed, 17 insertions, 4 deletions
diff --git a/libavformat/url.h b/libavformat/url.h
index 265a8ab2b6..b3eafa63c7 100644
--- a/libavformat/url.h
+++ b/libavformat/url.h
@@ -1,19 +1,19 @@
 /*
  *
- * This file is part of Libav.
+ * This file is part of FFmpeg.
  *
- * Libav is free software; you can redistribute it and/or
+ * FFmpeg is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
- * Libav is distributed in the hope that it will be useful,
+ * FFmpeg is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with Libav; if not, write to the Free Software
+ * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
@@ -59,6 +59,19 @@ typedef struct URLProtocol {
      * for those nested protocols.
      */
     int     (*url_open2)(URLContext *h, const char *url, int flags, AVDictionary **options);
+
+    /**
+     * Read data from the protocol.
+     * If data is immediately available (even less than size), EOF is
+     * reached or an error occurs (including EINTR), return immediately,
+     * Otherwise:
+     * In non-blocking mode, return AVERROR(EAGAIN) immediately.
+     * In blocking mode, wait for data/EOF/error with a short timeout (0.1s),
+     * and return AVERROR(EAGAIN) on timeout.
+     * Checking interrupt_callback, looping on EINTR and EAGAIN and until
+     * enough data has been read is left to the calling function; see
+     * retry_transfer_wrapper in avio.c.
+     */
     int     (*url_read)( URLContext *h, unsigned char *buf, int size);
     int     (*url_write)(URLContext *h, const unsigned char *buf, int size);
     int64_t (*url_seek)( URLContext *h, int64_t pos, int whence);