Doxument url_close().

Originally committed as revision 21420 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/avio.h

@@ -103,7 +103,16 @@ int url_read(URLContext *h, unsigned char *buf, int size);
 int url_read_complete(URLContext *h, unsigned char *buf, int size);
 int url_write(URLContext *h, unsigned char *buf, int size);
 int64_t url_seek(URLContext *h, int64_t pos, int whence);
+
+/**
+ * Closes the resource accessed by the URLContext h, and frees the
+ * memory used by it.
+ *
+ * @return a negative value if an error condition occurred, 0
+ * otherwise
+ */
 int url_close(URLContext *h);
+
 int url_exist(const char *filename);
 int64_t url_filesize(URLContext *h);