(1) os.system
仅仅在一个子终端运行系统命令,而不能获取命令执行后的返回信息
system(command) -> exit_status Execute the command (a string) in a subshell.
如果再命令行下执行,结果直接打印出来
>>> 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
该方法不但执行命令还返回执行后的信息对象
popen(command [, mode='r' [, bufsize]]) -> pipe Open a pipe to/from a command returning a file object.
例如:
>>>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 ']
好处在于:将返回的结果赋于一变量,便于程序的处理。
(3) 使用模块 subprocess
>>> import subprocess >>> subprocess.call(["cmd", "arg1", "arg2"],shell=True)
获取返回和输出:
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) 使用模块 commands
>>> 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: 当执行命令的参数或者返回中包含了中文文字,那么建议使用subprocess,如果使用os.popen则会出现下面的错误:
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)