28 lines
740 B
Python
28 lines
740 B
Python
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# follow.py
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import os
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import time
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def follow(filename):
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'''
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Generator that produces a sequence of lines being written at the end of a file.
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'''
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with open(filename,'r') as f:
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f.seek(0,os.SEEK_END)
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while True:
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line = f.readline()
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if line == '':
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time.sleep(0.1) # Sleep briefly to avoid busy wait
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continue
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yield line
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# Example use
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if __name__ == '__main__':
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for line in follow('../../Data/stocklog.csv'):
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fields = line.split(',')
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name = fields[0].strip('"')
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price = float(fields[1])
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change = float(fields[4])
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if change < 0:
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print('%10s %10.2f %10.2f' % (name, price, change))
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