Python 中执行系统命令
0x00 使用模块
在python执行系统命令一般可以通过3个模块来实现，这三个模块是：os、commands、subprocess
0x01 os模块执行系统命令
一般用os模块的system函数来执行一些简单的命令
>>> import os
>>> os.system("pwd")
/Users/reber
0
0x02 commands模块执行系统命令
commands这个模块在python3中被移除了
>>> import commands
>>> commands.getoutput("pwd")
'/Users/reber'
>>> commands.getstatusoutput("pwd")
(0, '/Users/reber') #返回状态码以及结果
0x03 subprocess模块执行系统命令
- task.py代码
def aaa():
s = 0
for x in range(3):
time.sleep(1)
s += x
return s
print(aaa())
- call函数执行命令(会阻塞到任务完成)
函数原型：subprocess.call(args, *, stdin=None, stdout=None, stderr=None, shell=False)
>>> from subprocess import call
>>> call(["ls","-l"]) #传入一个list
total 16
-rw-r--r-- 1 reber staff 80 8 16 16:19 README.md
drwxr-xr-x@ 3 reber staff 102 3 14 2017 archetypes
-rwxr-xr-x@ 1 reber staff 1403 12 13 17:43 config.toml
drwxr-xr-x@ 4 reber staff 136 12 9 23:02 content
drwxr-xr-x@ 7 reber staff 238 4 26 2017 layouts
drwxr-xr-x@ 19 reber staff 646 10 11 12:33 public
drwxr-xr-x@ 7 reber staff 238 10 11 12:33 static
0
>>> call("ls -l",shell=True) #shell设置为True时可以传入一个字符串
total 16
-rw-r--r-- 1 reber staff 80 8 16 16:19 README.md
drwxr-xr-x@ 3 reber staff 102 3 14 2017 archetypes
-rwxr-xr-x@ 1 reber staff 1403 12 13 17:43 config.toml
drwxr-xr-x@ 4 reber staff 136 12 9 23:02 content
drwxr-xr-x@ 7 reber staff 238 4 26 2017 layouts
drwxr-xr-x@ 19 reber staff 646 10 11 12:33 public
drwxr-xr-x@ 7 reber staff 238 10 11 12:33 static
0
- Popen函数进行进程交互(非阻塞)
>>> from subprocess import Popen,PIPE,STDOUT
>>> h = Popen("ls dsfj",stdout=PIPE,stderr=STDOUT,shell=True)
>>> h.stdout.read() #从数据流中读出数据，如果数据流过大且不读数据的话可能会死锁
'ls: dsfj: No such file or directory\n'
>>> h.stderr.read() #使用的是STDOUT，将错误通过标准输出流输出，没有read方法
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: 'NoneType' object has no attribute 'read'
>>> h = Popen("ls dsfj",stdout=PIPE,stderr=PIPE,shell=True)
>>> h.stdout.read()
''
>>> h.stderr.read()
'ls: dsfj: No such file or directory\n'
>>> cmd = "python /Users/reber/Desktop/task.py"
>>> h = Popen(cmd, stdout=PIPE, stderr=PIPE, shell=True)
>>> stdoutput = h.stdout.read() #stdoutput,erroutput = h.communicate()
>>> erroutput = h.stdout.read()
>>> stdoutput,erroutput
('3\n', '')
>>> h.pid,h.poll() #子进程id，执行结果状态码(0代表成功)
(49787, 0)
>>> f = open('a.txt','a+')
>>> h = Popen("ls -l", stdout=f, stderr=PIPE, shell=True) #写入文件
>>> h = Popen("ifconfig", shell=True, stdout=f, stderr=PIPE)
>>> f.close()
- 在python3中subprocess实现了commands的getstatusoutput方法
$ py3
(py3env) [16:28 reber@wyb in ~/wyb0.com git:(master) ✗]
$ python
Python 3.6.3 (default, Oct 4 2017, 06:09:15)
[GCC 4.2.1 Compatible Apple LLVM 9.0.0 (clang-900.0.37)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> from subprocess import getstatusoutput
>>> cmd = "python /Users/reber/Desktop/task.py"
>>> getstatusoutput(cmd)
(0, '3')