Python執行Linux系統指令的4種方法

(1) os.system

僅在一個子終端運行系統命令，而不能獲取命令執行後的返回資訊

system(command) -> exit_status
Execute the command (a string) in a subshel​​l.

若再命令列下執行，結果直接列印出來

>>> os.system('ls')

04101419778.CHM   bash      doc      books     downloads   Pictures  python
all-20061022      Desktop   Examples    project tools

(2) os.popen

此方法不但執行指令也傳回執行後的訊息物件

popen(command [, mode='r' [, bufsize]]) -> pipe

Open a pipe to/ from a command returning a file object.

>>>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_pickleklerecs.. peopleinteract_query.py ',
'reader.py ',
'testargv.py ',
'teststreams.py ',
'update_db_pickle.py ',
'writer.py ']

好處在於賦予傳回的結果於一變量，便於程序的處理。

(3)  使用模組subprocess

>>> import subprocess

>>> subprocess.call(["cmd", "arg1", "arg2"],shell=True)

:

傳回
import subprocess
p = subprocess.Popen('ls', shell=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)

for line in p.stdout.readlines():

.wait()

(4)  使用模組commands

>>> import commands
>>> dir(commands)
['__all__', '_____ 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:

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)

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