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Python实现文件阅读功能(Python学习笔记)

2015-06-10 09:40  DataBases  阅读(388)  评论(0编辑  收藏  举报

#!/usr/bin/python
# Filename: filereader.py
import sys

def readfile(filename):
  '''Print a file to the standard output.'''
  f = file(filename)
  while True:
    line = f.readline()
    if len(line) == 0:
      break
    print line,
  f.close()

if len(sys.argv) < 2:
  print 'No action specified.'
  sys.exit()

if sys.argv[1].startswith('--'):
  option = sys.argv[1][2:]
  if option == 'version':
    print 'Version 1.2'
  elif option == 'help':
    print '''\
      This program prints files to the standard output.
      Any number of files can be specified.
      Options include:
      --version: Prints the version number
      --help : Display this help'''
  else:
    print 'Unknown option.'
sys.exit()
else:
  for filename in sys.argv[1:]:
    readfile(filename)