diff -r 65f96010b35c Lib/test/test_os_jy.py
--- a/Lib/test/test_os_jy.py	Fri Feb 06 20:21:15 2015 -0700
+++ b/Lib/test/test_os_jy.py	Fri Feb 20 14:34:11 2015 -0800
@@ -58,6 +58,21 @@
             else:
                 self.assertTrue(False)
 
+    def test_issue2068(self):
+        os.remove(test_support.TESTFN)
+        for i in range(2):
+            fd = os.open(test_support.TESTFN, os.O_RDWR | os.O_CREAT | os.O_APPEND)
+            try:
+                os.write(fd, bytes('one'))
+                os.write(fd, bytes('two'))
+                os.write(fd, bytes('three'))
+            finally:
+                fd.close()
+
+        with open(test_support.TESTFN, 'rb') as f:
+            content = f.read()
+        self.assertEqual(content, 2 * b'onetwothree')
+
 
 class OSDirTestCase(unittest.TestCase):
 
diff -r 65f96010b35c src/org/python/core/io/FileIO.java
--- a/src/org/python/core/io/FileIO.java	Fri Feb 06 20:21:15 2015 -0700
+++ b/src/org/python/core/io/FileIO.java	Fri Feb 20 14:34:11 2015 -0800
@@ -307,7 +307,7 @@
         checkWritable();
         try {
             return !emulateAppend ? fileChannel.write(buf) :
-                    fileChannel.write(buf, fileChannel.position());
+                    fileChannel.write(buf, fileChannel.size());
         } catch (IOException ioe) {
             throw Py.IOError(ioe);
         }
@@ -344,7 +344,7 @@
             if (!buf.hasRemaining()) {
                 continue;
             }
-            if ((bufCount = fileChannel.write(buf, fileChannel.position())) == 0) {
+            if ((bufCount = fileChannel.write(buf, fileChannel.size())) == 0) {
                 break;
             }
             count += bufCount;