--- serialposix.py	2014-10-19 18:10:18.890542515 +0200
+++ serialposix-patched.py	2014-10-19 18:13:42.680841412 +0200
@@ -272,7 +272,7 @@
 
 
 class PosixSerial(SerialBase):
-    """Serial port class POSIX implementation. Serial port configuration is 
+    """Serial port class POSIX implementation. Serial port configuration is
     done with termios and fcntl. Runs on Linux and many other Un*x like
     systems."""
 
@@ -619,8 +619,8 @@
         This will send XON (true) and XOFF (false) to the other device.
         WARNING: this function is not portable to different platforms!
         """
-        if not self.hComPort: raise portNotOpenError
-        if enable:
+        if not self._isOpen: raise portNotOpenError
+        if level:
             termios.tcflow(self.fd, TERMIOS.TCION)
         else:
             termios.tcflow(self.fd, TERMIOS.TCIOFF)
@@ -676,7 +676,7 @@
                     #  handled below
                 buf = os.read(self.fd, size - len(read))
                 read.extend(buf)
-                if ((self._timeout is not None and self._timeout >= 0) or 
+                if ((self._timeout is not None and self._timeout >= 0) or
                     (self._interCharTimeout is not None and self._interCharTimeout > 0)) and not buf:
                     break   # early abort on timeout
         return bytes(read)