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diff --git a/examples/enhancedserial.py b/examples/enhancedserial.py
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+#!/usr/bin/env python
+"""Enhanced Serial Port class
+part of pyserial (http://pyserial.sf.net)  (C)2002 cliechti@gmx.net
+
+another implementation of the readline and readlines method.
+this one should be more efficient because a bunch of characters are read
+on each access, but the drawback is that a timeout must be specified to
+make it work (enforced by the class __init__).
+
+this class could be enhanced with a read_until() method and more
+like found in the telnetlib.
+"""
+
+from serial import Serial
+
+class EnhancedSerial(Serial):
+    def __init__(self, *args, **kwargs):
+        #ensure that a reasonable timeout is set
+        timeout = kwargs.get('timeout',0.1)
+        if timeout < 0.01: timeout = 0.1
+        kwargs['timeout'] = timeout
+        Serial.__init__(self, *args, **kwargs)
+        self.buf = ''
+        
+    def readline(self, maxsize=None, timeout=1):
+        """maxsize is ignored, timeout in seconds is the max time that is way for a complete line"""
+        tries = 0
+        while 1:
+            self.buf += self.read(512)
+            pos = self.buf.find('\n')
+            if pos >= 0:
+                line, self.buf = self.buf[:pos+1], self.buf[pos+1:]
+                return line
+            tries += 1
+            if tries * self.timeout > timeout:
+                break
+        line, self.buf = self.buf, ''
+        return line
+
+    def readlines(self, sizehint=None, timeout=1):
+        """read all lines that are available. abort after timout
+        when no more data arrives."""
+        lines = []
+        while 1:
+            line = self.readline(timeout=timeout)
+            if line:
+                lines.append(line)
+            if not line or line[-1:] != '\n':
+                break
+        return lines
+
+if __name__=='__main__':
+    #do some simple tests with a Loopback HW (see test.py for details)
+    PORT = 0
+    #test, only with Loopback HW (shortcut RX/TX pins (3+4 on DSUB 9 and 25) )
+    s = EnhancedSerial(PORT)
+    #write out some test data lines
+    s.write('\n'.join("hello how are you".split()))
+    #and read them back
+    print s.readlines()
+    #this one should print an empty list
+    print s.readlines(timeout=0.4)