How to write a file generator
tjreedy at udel.edu
Tue Jul 12 20:02:15 CEST 2011
On 7/12/2011 10:46 AM, 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
> raise StopIteration
Please use spaces rather than (disappearing) tabs in posted code.
> 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.
The same way you currently decide when to raise StopIteration
with open(filename, 'rb') as f:
When the caller gets '', it should go and do something else for awhile.
Terry Jan Reedy
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