(1) os.system
僅僅在一個子終端運行系統命令，而不能擷取命令執行後的返回資訊
複製代碼 代碼如下:
system(command) -> exit_status
Execute the command (a string) in a subshell.
如果再命令列下執行，結果直接列印出來
複製代碼 代碼如下:
>>> os.system('ls')
04101419778.CHM bash document media py-django video
11.wmv books downloads Pictures python
all-20061022 Desktop Examples project tools
(2) os.popen
該方法不但執行命令還返回執行後的資訊對象
複製代碼 代碼如下:
popen(command [, mode='r' [, bufsize]]) -> pipe
Open a pipe to/from a command returning a file object.
例如：
複製代碼 代碼如下:
>>>tmp = os.popen('ls *.py').readlines()
>>>tmp
Out[21]:
['dump_db_pickle.py ',
'dump_db_pickle_recs.py ',
'dump_db_shelve.py ',
'initdata.py ',
'__init__.py ',
'make_db_pickle.py ',
'make_db_pickle_recs.py ',
'make_db_shelve.py ',
'peopleinteract_query.py ',
'reader.py ',
'testargv.py ',
'teststreams.py ',
'update_db_pickle.py ',
'writer.py ']
好處在於：將返回的結果賦於一變數，便於程式的處理。
(3) 使用模組 subprocess
複製代碼 代碼如下:
>>> import subprocess
>>> subprocess.call(["cmd", "arg1", "arg2"],shell=True)
擷取返回和輸出:
複製代碼 代碼如下:
import subprocess
p = subprocess.Popen('ls', shell=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
for line in p.stdout.readlines():
print line,
retval = p.wait()
(4) 使用模組 commands
複製代碼 代碼如下:
>>> import commands
>>> dir(commands)
['__all__', '__builtins__', '__doc__', '__file__', '__name__', 'getoutput', 'getstatus','getstatusoutput', 'mk2arg', 'mkarg']
>>> commands.getoutput("date")
'Wed Jun 10 19:39:57 CST 2009'
>>>
>>> commands.getstatusoutput("date")
(0, 'Wed Jun 10 19:40:41 CST 2009')
注意： 當執行命令的參數或者返回中包含了中文文字，那麼建議使用subprocess，如果使用os.popen則會出現下面的錯誤:
複製代碼 代碼如下:
Traceback (most recent call last):
File "./test1.py", line 56, inmain()
File "./test1.py", line 45, in main
fax.sendFax()
File "./mailfax/Fax.py", line 13, in sendFax
os.popen(cmd)
UnicodeEncodeError: 'ascii' codec can't encode characters in position 46-52: ordinal not inrange(128)
