subprocess

[root@wesley ~]# python
Python 2.7.14 (default, Sep 10 2018, 23:42:00)
[GCC 4.4.7 20120313 (Red Hat 4.4.7-23)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>>
>>>
>>> import subprocess
>>> ret = subprocess.call('ls -l',shell=True)       #直接运行命令并打印 shell=True 表示程序将通过shell来执行
total 20
-rw-------. 1 root root  963 Jul  8 07:07 anaconda-ks.cfg
-rw-r--r--. 1 root root 8845 Jul  8 07:07 install.log
-rw-r--r--. 1 root root 3384 Jul  8 07:06 install.log.syslog
>>> ret=subprocess.call('ls -l',shell=False)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python2.7/subprocess.py", line 168, in call
    return Popen(*popenargs, **kwargs).wait()
  File "/usr/local/lib/python2.7/subprocess.py", line 390, in __init__
    errread, errwrite)
  File "/usr/local/lib/python2.7/subprocess.py", line 1025, in _execute_child
    raise child_exception
OSError: [Errno 2] No such file or directory
>>> subprocess.check_call('ls -l',shell=True)      #检查call 的执行命令，如果执行状态码是 0 ，则返回0，否则抛异常
total 20
-rw-------. 1 root root  963 Jul  8 07:07 anaconda-ks.cfg
-rw-r--r--. 1 root root 8845 Jul  8 07:07 install.log
-rw-r--r--. 1 root root 3384 Jul  8 07:06 install.log.syslog
0
>>> subprocess.check_call('exit 1',shell=True)          
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python2.7/subprocess.py", line 186, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command 'exit 1' returned non-zero exit status 1
>>> subprocess.check_output('echo','hello')    
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python2.7/subprocess.py", line 212, in check_output
    process = Popen(stdout=PIPE, *popenargs, **kwargs)
  File "/usr/local/lib/python2.7/subprocess.py", line 339, in __init__
    raise TypeError("bufsize must be an integer")
TypeError: bufsize must be an integer
>>> subprocess.check_output(['echo','hello'])     #args 是一个字符串或者元祖，列表（统一在某一个里面）
'hello
'
>>> subprocess.check_output('echo hello',shell=True)
'hello
'
>>> ret1=subprocess.Popen('mkdir t2',shell=True)
>>> subprocee.Popen('ls -l',shell=True)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'subprocee' is not defined
>>> subprocess.Popen('ls -l',shell=True)          #Popen执行命令
<subprocess.Popen object at 0x7f5e8b43f850>
>>> total 24
-rw-------. 1 root root  963 Jul  8 07:07 anaconda-ks.cfg
-rw-r--r--. 1 root root 8845 Jul  8 07:07 install.log
-rw-r--r--. 1 root root 3384 Jul  8 07:06 install.log.syslog
drwxr-xr-x. 2 root root 4096 Oct 16 03:15 t2

>>> subprocess.Popen('ifconfig',shell=True)
<subprocess.Popen object at 0x7f5e84f3dbd0>
>>> eth0      Link encap:Ethernet  HWaddr 00:0C:29:04:FE:91
          inet addr:192.168.159.128  Bcast:192.168.159.255  Mask:255.255.255.0
          inet6 addr: fe80::20c:29ff:fe04:fe91/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:1477 errors:0 dropped:0 overruns:0 frame:0
          TX packets:715 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:129113 (126.0 KiB)  TX bytes:87399 (85.3 KiB)

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)


>>> obj=subprocess.Popen('python',stdin=subprocess.PIPE,      
 #在python 环境里面执行命令，
注意：如果希望通过进程的stdin向其发送数据，在创建Popen对象的时候，
参数stdin必须被设置为PIPE。同样，
如果希望从stdout和stderr获取数据，必须将stdout和stderr设置为PIPE。
... stdout=subprocess.PIPE,stderr=subprocess.PIPE, 
... universal_newlines=True)
>>> obj.stdin.write('print(1)
')
>>> obj.stdin.write('print(2)')    #写入数据
>>> obj.stdin.close()
>>> cmd_out=obj.stdout.read() #取数据
>>> obj.stdout.close()
>>> cmd_error=obj.stderr.read()
>>> obj.stderr.close()
>>> print(cmd_out)
1
2

>>> print(cmd_error)

>>> obj=subprocess.Popen('python',stdin=subprocess.PIPE, 
... stdout=subprocess.PIPE,stderr=subprocess.PIPE, 
... universal_newlines=True)
...   File "<stdin>", line 2
    ... stdout=subprocess.PIPE,stderr=subprocess.PIPE, 
    ^
SyntaxError: invalid syntax
>>>   File "<stdin>", line 1
    ... universal_newlines=True)
    ^
SyntaxError: invalid syntax
>>> import subprocess

obj = subprocess.Popen(["python"], stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE, universal_newlines=True)
obj.stdin.write("print(1)
")
obj.stdin.write("print(2)")

out_error_list = obj.communicate() #取数据
print(out_error_list)>>> >>> >>> >>> >>> >>> >>>
('1
2
', '')
>>> import subprocess

obj = subprocess.Popen(["python"], stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE, universal_newlines=True)
out_error_list = obj.communicate('print("hello")') #写入并取数据 obj.communicate(input)
print(out_error_list)>>> >>> >>> >>>
('hello
', '')
>>>