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Date: Tue, 12 Jul 2011 17:52:50 +0200
From: Thomas Jollans <t@jollybox.de>
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Subject: Re: How to write a file generator
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On 07/12/2011 04:46 PM, Billy Mays wrote:
> I want to make a generator that will return lines from the tail of
> /var/log/syslog if there are any, but my function is reopening the file
> each call:
> 
> def getLines():
>     with open('/var/log/syslog', 'rb') as f:
>         while True:
>             line = f.readline()
>             if line:
>                 yield line
>             else:
>                 raise StopIteration
> 
> 
> I know the problem lies with the StopIteration, but I'm not sure how to
> tell the caller that there are no more lines for now.
> 
> -- 
> Bill

http://stackoverflow.com/questions/1475950/tail-f-in-python-with-no-time-sleep