import sys,os  
print sys.argv 
os.system(sys.argv[1]) 

#!/usr/bin/env python  
#_*_ coding:utf-8 _*_  
import sys   
def readfile(filename): #定义readfile函数，从文件中读出文件内容   
  '''''''''Print a file to the standard output.'''   
  f = file(filename)   
  while True:   
    line = f.readline()   
    if len(line) == 0:   
      break   
    print line, # notice comma 分别输出每行内容   
  f.close()   
# Script starts from here  
print sys.argv  
if len(sys.argv) < 2:   
  print 'No action specified.'   
  sys.exit()   
if sys.argv[1].startswith('--'):   
  option = sys.argv[1][2:]   
  # fetch sys.argv[1] but without the first two characters   
  if option == 'version': #当命令行参数为-- version，显示版本号   
    print 'Version 1.2'   
  elif option == 'help': #当命令行参数为--help时，显示相关帮助内容   
    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:]: #当参数为文件名时，传入readfile，读出其内容   
    readfile(filename)  

C:\Users\91135\Desktop>python sample.py
 ['sample.py']
No action specified.
C:\Users\91135\Desktop>python sample.py --help
['sample.py', '--help']
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
C:\Users\91135\Desktop>python sample.py --version
 ['sample.py', '--version']
Version 1.2
C:\Users\91135\Desktop>python sample.py --ok
 ['sample.py', '--ok']
Unknown option.
C:\Users\91135\Desktop>python sample.py test.txt
 ['sample.py', 'test.txt']
hello python!
C:\Users\91135\Desktop>python sample.py test.txt test1.txt test2.txt
 ['sample.py', 'test.txt', 'test1.txt', 'test2.txt']
 hello python!
 hello world!
hello wahaha!
goodbye!
C:\Users\91135\Desktop>