Rename blahHandler to onBlah throughout dart:io.

runtime/bin/file_impl.dart

Index: runtime/bin/file_impl.dart
diff --git a/runtime/bin/file_impl.dart b/runtime/bin/file_impl.dart
index d37ad893c94b15082f8636ad892c1b0ef89b61df..98f35d07ba8715cb0e1a306ef1a57530e5815b76 100644
--- a/runtime/bin/file_impl.dart
+++ b/runtime/bin/file_impl.dart
@@ -7,15 +7,14 @@ class _FileInputStream extends _BaseDataInputStream implements InputStream {
     _file = new File(name);
     _data = [];
     _position = 0;
-    _file.errorHandler = (String s) {
+    _file.onError = (String s) {
       if (_clientErrorHandler != null) {
         _clientErrorHandler();
       }
     };
-    _file.open();
-    _file.openHandler = (openedFile) {
+    _file.open(FileMode.READ, (openedFile) {
       _readDataFromFile(openedFile);
-    };
+    });
   }
 
   _FileInputStream.fromStdio(int fd) {
@@ -27,17 +26,15 @@ class _FileInputStream extends _BaseDataInputStream implements InputStream {
   }
 
   void _readDataFromFile(RandomAccessFile openedFile) {
-    openedFile.errorHandler = (String s) {
+    openedFile.onError = (String s) {
       if (_clientErrorHandler != null) {
         _clientErrorHandler();
       }
     };
-    openedFile.length();
-    openedFile.lengthHandler = (length) {
+    openedFile.length((length) {
       var contents = new ByteArray(length);
       if (length != 0) {
-        openedFile.readList(contents, 0, length);
-        openedFile.readListHandler = (read) {
+        openedFile.readList(contents, 0, length, (read) {
           if (read != length) {
             if (_clientErrorHandler != null) {
               _clientErrorHandler();
@@ -45,20 +42,18 @@ class _FileInputStream extends _BaseDataInputStream implements InputStream {
           } else {
             _data = contents;
           }
-          openedFile.close();
-          openedFile.closeHandler = () {
+          openedFile.close(() {
             _streamMarkedClosed = true;
             _checkScheduleCallbacks();
-          };
-        };
+          });
+        });
       } else {
-        openedFile.close();
-        openedFile.closeHandler = () {
+        openedFile.close(() {
           _streamMarkedClosed = true;
           _checkScheduleCallbacks();
-        };
-      };
-    };
+        });
+      }
+    });
   }
 
   int available() {
@@ -100,14 +95,13 @@ class _FileOutputStream implements OutputStream {
   _FileOutputStream(String name, FileMode mode) {
     _pendingOperations = new List<List<int>>();
     var f = new File(name);
-    f.open(mode);
-    f.openHandler = (openedFile) {
+    f.open(mode, (openedFile) {
       _file = openedFile;
       _setupFileHandlers();
       _processPendingOperations();
-    };
-    f.errorHandler = (e) {
-      if (_errorHandler != null) _errorHandler();
+    });
+    f.onError = (e) {
+      if (_onError != null) _onError();
     };
   }
 
@@ -119,17 +113,14 @@ class _FileOutputStream implements OutputStream {
 
 
   void _setupFileHandlers() {
-    _file.errorHandler = (e) {
-      if (_errorHandler != null) _errorHandler();
+    _file.onError = (e) {
+      if (_onError != null) _onError();
     };
-    _file.noPendingWriteHandler = () {
-      if (!_streamMarkedClosed && _noPendingWriteHandler != null) {
-        _noPendingWriteHandler();
+    _file.onNoPendingWrites = () {
+      if (!_streamMarkedClosed && _onNoPendingWrites != null) {
+        _onNoPendingWrites();
       }
     };
-    _file.closeHandler = () {
-      if (_closeHandler != null) _closeHandler();
-    };
   }
 
   bool write(List<int> buffer, [bool copyBuffer = false]) {
@@ -163,21 +154,23 @@ class _FileOutputStream implements OutputStream {
     if (_file == null) {
       _pendingOperations.add(null);
     } else if (!_streamMarkedClosed) {
-      _file.close();
+      _file.close(() {
+        if (_onClosed != null) _onClosed();
+      });
       _streamMarkedClosed = true;
     }
   }
 
-  void set noPendingWriteHandler(void callback()) {
-    _noPendingWriteHandler = callback;
+  void set onNoPendingWrites(void callback()) {
+    _onNoPendingWrites = callback;
   }
 
-  void set closeHandler(void callback()) {
-    _closeHandler = callback;
+  void set onClosed(void callback()) {
+    _onClosed = callback;
   }
 
-  void set errorHandler(void callback()) {
-    _errorHandler = callback;
+  void set onError(void callback()) {
+    _onError = callback;
   }
 
   void _processPendingOperations() {
@@ -205,9 +198,9 @@ class _FileOutputStream implements OutputStream {
   // file was successfully opened.
   List<List<int>> _pendingOperations;
 
-  Function _noPendingWriteHandler;
-  Function _closeHandler;
-  Function _errorHandler;
+  Function _onNoPendingWrites;
+  Function _onClosed;
+  Function _onError;
 }
 
 
@@ -325,12 +318,12 @@ class _File implements File {
   // Constructor for file.
   _File(String this._name) : _asyncUsed = false;
 
-  void exists() {
+  void exists(void callback(bool exists)) {
     _ensureFileService();
     _asyncUsed = true;
     if (_name is !String) {
-      if (_errorHandler != null) {
-        _errorHandler('File name is not a string: $_name');
+      if (_onError != null) {
+        _onError('File name is not a string: $_name');
       }
       return;
     }
@@ -338,7 +331,7 @@ class _File implements File {
     request[0] = _FileUtils.kExistsRequest;
     request[1] = _name;
     _fileService.call(request).receive((exists, replyTo) {
-      if (_existsHandler != null) _existsHandler(exists);
+      callback(exists);
     });
   }
 
@@ -353,7 +346,7 @@ class _File implements File {
     return _FileUtils.exists(_name);
   }
 
-  void create() {
+  void create(void callback()) {
     _ensureFileService();
     _asyncUsed = true;
     List request = new List(2);
@@ -361,9 +354,9 @@ class _File implements File {
     request[1] = _name;
     _fileService.call(request).receive((created, replyTo) {
       if (created) {
-        if (_createHandler != null) _createHandler();
-      } else if (_errorHandler != null) {
-        _errorHandler("Cannot create file: $_name");
+        callback();
+      } else if (_onError != null) {
+        _onError("Cannot create file: $_name");
       }
     });
   }
@@ -379,7 +372,7 @@ class _File implements File {
     }
   }
 
-  void delete() {
+  void delete(void callback()) {
     _ensureFileService();
     _asyncUsed = true;
     List request = new List(2);
@@ -387,9 +380,9 @@ class _File implements File {
     request[1] = _name;
     _fileService.call(request).receive((deleted, replyTo) {
       if (deleted) {
-        if (_deleteHandler != null) _deleteHandler();
-      } else if (_errorHandler != null) {
-        _errorHandler("Cannot delete file: $_name");
+        callback();
+      } else if (_onError != null) {
+        _onError("Cannot delete file: $_name");
       }
     });
   }
@@ -405,7 +398,7 @@ class _File implements File {
     }
   }
 
-  void directory() {
+  void directory(void callback(Directory dir)) {
     _ensureFileService();
     _asyncUsed = true;
     List request = new List(2);
@@ -413,9 +406,9 @@ class _File implements File {
     request[1] = _name;
     _fileService.call(request).receive((path, replyTo) {
       if (path != null) {
-        if (_directoryHandler != null) _directoryHandler(new Directory(path));
-      } else if (_errorHandler != null) {
-        _errorHandler("Cannot get directory for: ${_name}");
+        callback(new Directory(path));
+      } else if (_onError != null) {
+        _onError("Cannot get directory for: ${_name}");
       }
     });
   }
@@ -431,15 +424,15 @@ class _File implements File {
     return new Directory(_FileUtils.directory(_name));
   }
 
-  void open([FileMode mode = FileMode.READ]) {
+  void open(FileMode mode, void callback(RandomAccessFile file)) {
     _ensureFileService();
     _asyncUsed = true;
     if (mode != FileMode.READ &&
         mode != FileMode.WRITE &&
         mode != FileMode.APPEND) {
-      if (_errorHandler != null) {
-        _errorHandler("Unknown file mode. Use FileMode.READ, FileMode.WRITE " +
-                      "or FileMode.APPEND.");
+      if (_onError != null) {
+        _onError("Unknown file mode. Use FileMode.READ, FileMode.WRITE " +
+                 "or FileMode.APPEND.");
         return;
       }
     }
@@ -448,17 +441,10 @@ class _File implements File {
     request[1] = _name;
     request[2] = mode._mode;  // Direct int value for serialization.
     _fileService.call(request).receive((id, replyTo) {
-      var handler = _openHandler;
-      if (handler === null) {
-        // If no open handler is present, close the file immediately to
-        // avoid leaking an open file descriptor.
-        handler = (file) => file.close();
-      }
       if (id != 0) {
-        var randomAccessFile = new _RandomAccessFile(id, _name);
-        handler(randomAccessFile);
-      } else if (_errorHandler != null) {
-        _errorHandler("Cannot open file: $_name");
+        callback(new _RandomAccessFile(id, _name));
+      } else if (_onError != null) {
+        _onError("Cannot open file: $_name");
       }
     });
   }
@@ -489,7 +475,7 @@ class _File implements File {
     return new _RandomAccessFile(id, "");
   }
 
-  void fullPath() {
+  void fullPath(void callback(String result)) {
     _ensureFileService();
     _asyncUsed = true;
     List request = new List(2);
@@ -497,9 +483,9 @@ class _File implements File {
     request[1] = _name;
     _fileService.call(request).receive((result, replyTo) {
       if (result != null) {
-        if (_fullPathHandler != null) _fullPathHandler(result);
-      } else if (_errorHandler != null) {
-        _errorHandler("fullPath failed");
+        callback(result);
+      } else if (_onError != null) {
+        _onError("fullPath failed");
       }
     });
   }
@@ -529,22 +515,20 @@ class _File implements File {
     return new _FileOutputStream(_name, mode);
   }
 
-  void readAsBytes() {
+  void readAsBytes(void callback(List<int> bytes)) {
     _asyncUsed = true;
     var chunks = new _BufferList();
     var stream = openInputStream();
-    stream.closeHandler = () {
-      if (_readAsBytesHandler != null) {
-        _readAsBytesHandler(chunks.readBytes(chunks.length));
-      }
+    stream.onClosed = () {
+      callback(chunks.readBytes(chunks.length));
     };
-    stream.dataHandler = () {
+    stream.onData = () {
       var chunk = stream.read();
       chunks.add(chunk);
     };
-    stream.errorHandler = () {
-      if (_errorHandler != null) {
-        _errorHandler("Failed to read file as bytes: $_name");
+    stream.onError = () {
+      if (_onError != null) {
+        _onError("Failed to read file as bytes: $_name");
       }
     };
   }
@@ -561,7 +545,7 @@ class _File implements File {
     if (read != length) {
       throw new FileIOException("Failed reading file as bytes: $_name");
     }
-    opened.close();
+    opened.closeSync();
     return result;
   }
 
@@ -576,26 +560,23 @@ class _File implements File {
     throw new FileIOException("Unsupported encoding $_encoding");
   }
 
-  void readAsText([String encoding = "UTF-8"]) {
+  void readAsText(String encoding, void callback(String text)) {
     _asyncUsed = true;
     var decoder = _getDecoder(encoding);
-    readAsBytes();
-    readAsBytesHandler = (bytes) {
-      if (_readAsTextHandler != null) {
-        try {
-          decoder.write(bytes);
-        } catch (var e) {
-          if (_errorHandler != null) {
-            _errorHandler(e.toString());
-            return;
-          }
+    readAsBytes((bytes) {
+      try {
+        decoder.write(bytes);
+      } catch (var e) {
+        if (_onError != null) {
+          _onError(e.toString());
+          return;
         }
-        _readAsTextHandler(decoder.decoded);
       }
-    };
+      callback(decoder.decoded);
+    });
   }
 
-  String readAsTextSync([String encoding = "UTF-8"]) {
+  String readAsTextSync([String encoding = 'UTF-8']) {
     if (_asyncUsed) {
       throw new FileIOException(
           "Mixed use of synchronous and asynchronous API");
@@ -622,23 +603,20 @@ class _File implements File {
     return result;
   }
 
-  void readAsLines([String encoding = "UTF-8"]) {
+  void readAsLines(String encoding, void callback(List<String> lines)) {
     _asyncUsed = true;
     var decoder = _getDecoder(encoding);
-    readAsBytes();
-    readAsBytesHandler = (bytes) {
-      if (_readAsLinesHandler != null) {
-        try {
-          decoder.write(bytes);
-        } catch (var e) {
-          if (_errorHandler != null) {
-            _errorHandler(e.toString());
-            return;
-          }
+    readAsBytes((bytes) {
+      try {
+        decoder.write(bytes);
+      } catch (var e) {
+        if (_onError != null) {
+          _onError(e.toString());
+          return;
         }
-        _readAsLinesHandler(_getDecodedLines(decoder));
       }
-    };
+      callback(_getDecodedLines(decoder));
+    });
   }
 
   List<String> readAsLinesSync([String encoding = "UTF-8"]) {
@@ -654,44 +632,8 @@ class _File implements File {
 
   String get name() => _name;
 
-  void set existsHandler(void handler(bool exists)) {
-    _existsHandler = handler;
-  }
-
-  void set createHandler(void handler()) {
-    _createHandler = handler;
-  }
-
-  void set deleteHandler(void handler()) {
-    _deleteHandler = handler;
-  }
-
-  void set directoryHandler(void handler(Directory directory)) {
-    _directoryHandler = handler;
-  }
-
-  void set openHandler(void handler(RandomAccessFile file)) {
-    _openHandler = handler;
-  }
-
-  void set readAsBytesHandler(void handler(List<int> bytes)) {
-    _readAsBytesHandler = handler;
-  }
-
-  void set readAsTextHandler(void handler(String text)) {
-    _readAsTextHandler = handler;
-  }
-
-  void set readAsLinesHandler(void handler(List<String> lines)) {
-    _readAsLinesHandler = handler;
-  }
-
-  void set fullPathHandler(void handler(String)) {
-    _fullPathHandler = handler;
-  }
-
-  void set errorHandler(void handler(String error)) {
-    _errorHandler = handler;
+  void set onError(void handler(String error)) {
+    _onError = handler;
   }
 
   void _ensureFileService() {
@@ -705,23 +647,14 @@ class _File implements File {
 
   SendPort _fileService;
 
-  Function _existsHandler;
-  Function _createHandler;
-  Function _deleteHandler;
-  Function _directoryHandler;
-  Function _openHandler;
-  Function _readAsBytesHandler;
-  Function _readAsTextHandler;
-  Function _readAsLinesHandler;
-  Function _fullPathHandler;
-  Function _errorHandler;
+  Function _onError;
 }
 
 
 class _RandomAccessFile implements RandomAccessFile {
   _RandomAccessFile(int this._id, String this._name) : _asyncUsed = false;
 
-  void close() {
+  void close(void callback()) {
     if (_id == 0) return;
     _ensureFileService();
     _asyncUsed = true;
@@ -734,9 +667,9 @@ class _RandomAccessFile implements RandomAccessFile {
     _fileService.call(request).receive((result, replyTo) {
       if (result != -1) {
         _id = result;
-        if (_closeHandler != null) _closeHandler();
-      } else if (_errorHandler != null) {
-        _errorHandler("Cannot close file: $_name");
+        callback();
+      } else if (_onError != null) {
+        _onError("Cannot close file: $_name");
       }
     });
   }
@@ -753,7 +686,7 @@ class _RandomAccessFile implements RandomAccessFile {
     _id = id;
   }
 
-  void readByte() {
+  void readByte(void callback(int byte)) {
     _ensureFileService();
     _asyncUsed = true;
     List request = new List(2);
@@ -761,9 +694,9 @@ class _RandomAccessFile implements RandomAccessFile {
     request[1] = _id;
     _fileService.call(request).receive((result, replyTo) {
       if (result != -1) {
-        if (_readByteHandler != null) _readByteHandler(result);
-      } else if (_errorHandler != null) {
-        _errorHandler("readByte failed");
+        callback(result);
+      } else if (_onError != null) {
+        _onError("readByte failed");
       }
     });
   }
@@ -780,12 +713,13 @@ class _RandomAccessFile implements RandomAccessFile {
     return result;
   }
 
-  void readList(List<int> buffer, int offset, int bytes) {
+  void readList(List<int> buffer, int offset, int bytes,
+                void callback(int read)) {
     _ensureFileService();
     _asyncUsed = true;
     if (buffer is !List || offset is !int || bytes is !int) {
-      if (_errorHandler != null) {
-        _errorHandler("Invalid arguments to readList");
+      if (_onError != null) {
+        _onError("Invalid arguments to readList");
       }
       return;
     };
@@ -798,10 +732,10 @@ class _RandomAccessFile implements RandomAccessFile {
         var read = result[0];
         var data = result[1];
         buffer.setRange(offset, read, data);
-        if (_readListHandler != null) _readListHandler(read);
+        callback(read);
         return;
-      } else if (_errorHandler != null) {
-        _errorHandler(result is String ? result : "readList failed");
+      } else if (_onError != null) {
+        _onError(result is String ? result : "readList failed");
       }
     });
   }
@@ -831,8 +765,8 @@ class _RandomAccessFile implements RandomAccessFile {
     _ensureFileService();
     _asyncUsed = true;
     if (value is !int) {
-      if (_errorHandler != null) {
-        _errorHandler("Invalid argument to writeByte");
+      if (_onError != null) {
+        _onError("Invalid argument to writeByte");
       }
       return;
     }
@@ -843,8 +777,8 @@ class _RandomAccessFile implements RandomAccessFile {
     _writeEnqueued();
     _fileService.call(request).receive((result, replyTo) {
       _writeCompleted();
-      if (result == -1 && _errorHandler !== null) {
-        _errorHandler("writeByte failed");
+      if (result == -1 && _onError !== null) {
+        _onError("writeByte failed");
       }
     });
   }
@@ -868,8 +802,8 @@ class _RandomAccessFile implements RandomAccessFile {
     _ensureFileService();
     _asyncUsed = true;
     if (buffer is !List || offset is !int || bytes is !int) {
-      if (_errorHandler != null) {
-        _errorHandler("Invalid arguments to writeList");
+      if (_onError != null) {
+        _onError("Invalid arguments to writeList");
       }
       return;
     }
@@ -888,8 +822,8 @@ class _RandomAccessFile implements RandomAccessFile {
     _writeEnqueued();
     _fileService.call(request).receive((result, replyTo) {
       _writeCompleted();
-      if (result == -1 && _errorHandler !== null) {
-        _errorHandler("writeList failed");
+      if (result == -1 && _onError !== null) {
+        _onError("writeList failed");
       }
     });
   }
@@ -925,8 +859,8 @@ class _RandomAccessFile implements RandomAccessFile {
     _writeEnqueued();
     _fileService.call(request).receive((result, replyTo) {
       _writeCompleted();
-      if (result == -1 && _errorHandler !== null) {
-        _errorHandler("writeString failed");
+      if (result == -1 && _onError !== null) {
+        _onError("writeString failed");
       }
     });
   }
@@ -943,7 +877,7 @@ class _RandomAccessFile implements RandomAccessFile {
     return result;
   }
 
-  void position() {
+  void position(void callback(int position)) {
     _ensureFileService();
     _asyncUsed = true;
     List request = new List(2);
@@ -951,9 +885,9 @@ class _RandomAccessFile implements RandomAccessFile {
     request[1] = _id;
     _fileService.call(request).receive((result, replyTo) {
       if (result != -1) {
-        if (_positionHandler != null) _positionHandler(result);
-      } else if (_errorHandler != null) {
-        _errorHandler("position failed");
+        callback(result);
+      } else if (_onError != null) {
+        _onError("position failed");
       }
     });
   }
@@ -970,7 +904,7 @@ class _RandomAccessFile implements RandomAccessFile {
     return result;
   }
 
-  void setPosition(int position) {
+  void setPosition(int position, void callback()) {
     _ensureFileService();
     _asyncUsed = true;
     List request = new List(3);
@@ -979,9 +913,9 @@ class _RandomAccessFile implements RandomAccessFile {
     request[2] = position;
     _fileService.call(request).receive((result, replyTo) {
       if (result) {
-        if (_setPositionHandler != null) _setPositionHandler();
-      } else if (_errorHandler != null) {
-        _errorHandler("setPosition failed");
+        callback();
+      } else if (_onError != null) {
+        _onError("setPosition failed");
       }
     });
   }
@@ -998,7 +932,7 @@ class _RandomAccessFile implements RandomAccessFile {
     }
   }
 
-  void truncate(int length) {
+  void truncate(int length, void callback()) {
     _ensureFileService();
     _asyncUsed = true;
     List request = new List(3);
@@ -1007,9 +941,9 @@ class _RandomAccessFile implements RandomAccessFile {
     request[2] = length;
     _fileService.call(request).receive((result, replyTo) {
       if (result) {
-        if (_truncateHandler != null) _truncateHandler();
-      } else if (_errorHandler != null) {
-        _errorHandler("truncate failed");
+        callback();
+      } else if (_onError != null) {
+        _onError("truncate failed");
       }
     });
   }
@@ -1025,7 +959,7 @@ class _RandomAccessFile implements RandomAccessFile {
     }
   }
 
-  void length() {
+  void length(void callback(int length)) {
     _ensureFileService();
     _asyncUsed = true;
     List request = new List(2);
@@ -1033,9 +967,9 @@ class _RandomAccessFile implements RandomAccessFile {
     request[1] = _id;
     _fileService.call(request).receive((result, replyTo) {
       if (result != -1) {
-        if (_lengthHandler != null) _lengthHandler(result);
-      } else if (_errorHandler != null) {
-        _errorHandler("length failed");
+        callback(result);
+      } else if (_onError != null) {
+        _onError("length failed");
       }
     });
   }
@@ -1052,7 +986,7 @@ class _RandomAccessFile implements RandomAccessFile {
     return result;
   }
 
-  void flush() {
+  void flush(void callback()) {
     _ensureFileService();
     _asyncUsed = true;
     List request = new List(2);
@@ -1060,9 +994,9 @@ class _RandomAccessFile implements RandomAccessFile {
     request[1] = _id;
     _fileService.call(request).receive((result, replyTo) {
       if (result != -1) {
-        if (_flushHandler != null) _flushHandler();
-      } else if (_errorHandler != null) {
-        _errorHandler("flush failed");
+        callback();
+      } else if (_onError != null) {
+        _onError("flush failed");
       }
     });
   }
@@ -1080,51 +1014,19 @@ class _RandomAccessFile implements RandomAccessFile {
 
   String get name() => _name;
 
-  void set errorHandler(void handler(String error)) {
-    _errorHandler = handler;
-  }
-
-  void set closeHandler(void handler()) {
-    _closeHandler = handler;
-  }
-
-  void set readByteHandler(void handler(int byte)) {
-    _readByteHandler = handler;
+  void set onError(void handler(String error)) {
+    _onError = handler;
   }
 
-  void set readListHandler(void handler(int read)) {
-    _readListHandler = handler;
-  }
-
-  void set noPendingWriteHandler(void handler()) {
-    _noPendingWriteHandler = handler;
+  void set onNoPendingWrites(void handler()) {
+    _onNoPendingWrites = handler;
     if (_pendingWrites == 0) {
       _noPendingWriteTimer = new Timer((t) {
-        if (_noPendingWriteHandler != null) _noPendingWriteHandler();
+        if (_onNoPendingWrites != null) _onNoPendingWrites();
       }, 0);
     }
   }
 
-  void set positionHandler(void handler(int pos)) {
-    _positionHandler = handler;
-  }
-
-  void set setPositionHandler(void handler()) {
-    _setPositionHandler = handler;
-  }
-
-  void set truncateHandler(void handler()) {
-    _truncateHandler = handler;
-  }
-
-  void set lengthHandler(void handler(int length)) {
-    _lengthHandler = handler;
-  }
-
-  void set flushHandler(void handler()) {
-    _flushHandler = handler;
-  }
-
   void _ensureFileService() {
     if (_fileService == null) {
       _fileService = _FileUtils.newServicePort();
@@ -1141,8 +1043,8 @@ class _RandomAccessFile implements RandomAccessFile {
 
   void  _writeCompleted() {
     _pendingWrites--;
-    if (_pendingWrites == 0 && _noPendingWriteHandler != null) {
-      _noPendingWriteHandler();
+    if (_pendingWrites == 0 && _onNoPendingWrites != null) {
+      _onNoPendingWrites();
     }
   }
 
@@ -1156,14 +1058,6 @@ class _RandomAccessFile implements RandomAccessFile {
 
   Timer _noPendingWriteTimer;
 
-  Function _closeHandler;
-  Function _readByteHandler;
-  Function _readListHandler;
-  Function _noPendingWriteHandler;
-  Function _positionHandler;
-  Function _setPositionHandler;
-  Function _truncateHandler;
-  Function _lengthHandler;
-  Function _flushHandler;
-  Function _errorHandler;
+  Function _onNoPendingWrites;
+  Function _onError;
 }