--- a/src/luan/modules/IoLuan.java	Sat May 16 12:33:41 2020 +0300
+++ b/src/luan/modules/IoLuan.java	Sat May 16 17:56:02 2020 -0600
@@ -205,14 +205,7 @@
 		}
 
 		public long checksum() throws IOException, LuanException {
-			long cs = 0;
-			InputStream in = new BufferedInputStream(inputStream());
-			int c;
-			while( (c=in.read()) != -1 ) {
-				cs = 31 * cs + c;
-			}
-			in.close();
-			return cs;
+			return IoUtils.checksum( new BufferedInputStream(inputStream()) );
 		}
 
 		public String charset() {