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"""Enhanced Serial Port class
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part of pyserial (http://pyserial.sf.net) (C)2002 cliechti@gmx.net
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another implementation of the readline and readlines method.
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this one should be more efficient because a bunch of characters are read
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on each access, but the drawback is that a timeout must be specified to
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make it work (enforced by the class __init__).
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this class could be enhanced with a read_until() method and more
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like found in the telnetlib.
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from serial import Serial
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class EnhancedSerial(Serial):
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def __init__(self, *args, **kwargs):
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#ensure that a reasonable timeout is set
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timeout = kwargs.get('timeout',0.1)
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if timeout < 0.01: timeout = 0.1
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kwargs['timeout'] = timeout
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Serial.__init__(self, *args, **kwargs)
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def readline(self, maxsize=None, timeout=1):
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"""maxsize is ignored, timeout in seconds is the max time that is way for a complete line"""
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self.buf += self.read(512)
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pos = self.buf.find('\n')
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line, self.buf = self.buf[:pos+1], self.buf[pos+1:]
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if tries * self.timeout > timeout:
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line, self.buf = self.buf, ''
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def readlines(self, sizehint=None, timeout=1):
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"""read all lines that are available. abort after timout
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when no more data arrives."""
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line = self.readline(timeout=timeout)
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if not line or line[-1:] != '\n':
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if __name__=='__main__':
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#do some simple tests with a Loopback HW (see test.py for details)
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#test, only with Loopback HW (shortcut RX/TX pins (3+4 on DSUB 9 and 25) )
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s = EnhancedSerial(PORT)
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#write out some test data lines
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s.write('\n'.join("hello how are you".split()))
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#this one should print an empty list
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print s.readlines(timeout=0.4)
added
removed
pyserial-2.0/examples/enhancedserial.py
