python調(diào)用bash?shell腳本方法

更新時間：2022年01月25日 13:19:33 作者：maxwell-ma

這篇文章主要給大家分享了額python調(diào)用bash?shell腳本方法,os.system(command)、os.popen(command)等方法，具有一定的參考價值，需要的小伙伴可以參考一下，希望對你有所幫助

1. os.system()

help(os.system)

1.1. demo

os.system(command):該方法在調(diào)用完shell腳本后，返回一個16位的二進(jìn)制數(shù)，
低位為殺死所調(diào)用腳本的信號號碼，高位為腳本的退出狀態(tài)碼，
即腳本中exit 1的代碼執(zhí)行后，os.system函數(shù)返回值的高位數(shù)則是1，如果低位數(shù)是0的情況下，
則函數(shù)的返回值是0x0100,換算為十進(jìn)制得到256。
要獲得os.system的正確返回值，可以使用位移運算（將返回值右移8位）還原返回值：

>>> import os
>>> os.system("./test.sh")
hello python!
hello world!
256
>>> n>>8
1

2. os.popen()

help(os.system)

2.1 demo

os.popen(command):這種調(diào)用方式是通過管道的方式來實現(xiàn)，函數(shù)返回一個file對象，
里面的內(nèi)容是腳本輸出的內(nèi)容（可簡單理解為echo輸出的內(nèi)容），使用os.popen調(diào)用test.sh的情況

>> import os
>>> os.popen("./test.sh")
<open file './test.sh', mode 'r' at 0x7f6cbbbee4b0>
>>> f=os.popen("./test.sh")
>>> f
<open file './test.sh', mode 'r' at 0x7f6cbbbee540>
>>> f.readlines()
['hello python!\n', 'hello world!\n']

3. commands模塊

（1）commands.getstatusoutput(cmd)，其以字符串的形式返回的是輸出結(jié)果和狀態(tài)碼，即（status,output）。
（2）commands.getoutput(cmd)，返回cmd的輸出結(jié)果。
（3）commands.getstatus(file)，返回ls -l file的執(zhí)行結(jié)果字符串，調(diào)用了getoutput，不建議使用此方法

4. subprocess

subprocess模塊，允許創(chuàng)建很多子進(jìn)程，創(chuàng)建的時候能指定子進(jìn)程和子進(jìn)程的輸入、輸出、錯誤輸出管道，執(zhí)行后能獲取輸出結(jié)果和執(zhí)行狀態(tài)。

（1）subprocess.run()：python3.5中新增的函數(shù)，執(zhí)行指定的命令，等待命令執(zhí)行完成后返回一個包含執(zhí)行結(jié)果的CompletedProcess類的實例。
（2）subprocess.call()：執(zhí)行指定的命令，返回命令執(zhí)行狀態(tài)，功能類似os.system（cmd）。
（3）subprocess.check_call()：python2.5中新增的函數(shù), 執(zhí)行指定的命令, 如果執(zhí)行成功則返回狀態(tài)碼，否則拋出異常。

說明：subprocess.run(args, *, stdin=None, input=None, stdout=None, stderr=None, shell=False, timeout=None, check=False, universal_newlines=False)
subprocess.call(args, *, stdin=None, stdout=None, stderr=None, shell=False, timeout=None)
subprocess.check_call(args, *, stdin=None, stdout=None, stderr=None, shell=False, timeout=None)

args：表示shell指令，若以字符串形式給出shell指令，如"ls -l “則需要使shell = Ture。否則默認(rèn)已數(shù)組形式表示shell變量，如"ls”,"-l"。
當(dāng)使用比較復(fù)雜的shell語句時，可以先使用shlex模塊的shlex.split()方法來幫助格式化命令，然后在傳遞給run()方法或Popen。

4.1 demo

Stubs for subprocess

Based on http://docs.python.org/2/library/subprocess.html and Python 3 stub

from typing import Sequence, Any, Mapping, Callable, Tuple, IO, Union, Optional, List, Text

_FILE = Union[None, int, IO[Any]]
_TXT = Union[bytes, Text]
_CMD = Union[_TXT, Sequence[_TXT]]
_ENV = Union[Mapping[bytes, _TXT], Mapping[Text, _TXT]]

# Same args as Popen.__init__
def call(args: _CMD,
     bufsize: int = ...,
     executable: _TXT = ...,
     stdin: _FILE = ...,
     stdout: _FILE = ...,
     stderr: _FILE = ...,
     preexec_fn: Callable[[], Any] = ...,
     close_fds: bool = ...,
     shell: bool = ...,
     cwd: _TXT = ...,
     env: _ENV = ...,
     universal_newlines: bool = ...,
     startupinfo: Any = ...,
     creationflags: int = ...) -> int: ...

def check_call(args: _CMD,
        bufsize: int = ...,
        executable: _TXT = ...,
        stdin: _FILE = ...,
        stdout: _FILE = ...,
        stderr: _FILE = ...,
        preexec_fn: Callable[[], Any] = ...,
        close_fds: bool = ...,
        shell: bool = ...,
        cwd: _TXT = ...,
        env: _ENV = ...,
        universal_newlines: bool = ...,
        startupinfo: Any = ...,
        creationflags: int = ...) -> int: ...

# Same args as Popen.__init__ except for stdout
def check_output(args: _CMD,
         bufsize: int = ...,
         executable: _TXT = ...,
         stdin: _FILE = ...,
         stderr: _FILE = ...,
         preexec_fn: Callable[[], Any] = ...,
         close_fds: bool = ...,
         shell: bool = ...,
         cwd: _TXT = ...,
         env: _ENV = ...,
         universal_newlines: bool = ...,
         startupinfo: Any = ...,
         creationflags: int = ...) -> bytes: ...

PIPE = ... # type: int
STDOUT = ... # type: int

class CalledProcessError(Exception):
  returncode = 0
  # morally: _CMD
  cmd = ... # type: Any
  # morally: Optional[bytes]
  output = ... # type: Any

  def __init__(self,
         returncode: int,
         cmd: _CMD,
         output: Optional[bytes] = ...) -> None: ...

class Popen:
  stdin = ... # type: Optional[IO[Any]]
  stdout = ... # type: Optional[IO[Any]]
  stderr = ... # type: Optional[IO[Any]]
  pid = 0
  returncode = 0

  def __init__(self,
         args: _CMD,
         bufsize: int = ...,
         executable: Optional[_TXT] = ...,
         stdin: Optional[_FILE] = ...,
         stdout: Optional[_FILE] = ...,
         stderr: Optional[_FILE] = ...,
         preexec_fn: Optional[Callable[[], Any]] = ...,
         close_fds: bool = ...,
         shell: bool = ...,
         cwd: Optional[_TXT] = ...,
         env: Optional[_ENV] = ...,
         universal_newlines: bool = ...,
         startupinfo: Optional[Any] = ...,
         creationflags: int = ...) -> None: ...

  def poll(self) -> int: ...
  def wait(self) -> int: ...
  # morally: -> Tuple[Optional[bytes], Optional[bytes]]
  def communicate(self, input: Optional[_TXT] = ...) -> Tuple[Any, Any]: ...
  def send_signal(self, signal: int) -> None: ...
  def terminate(self) -> None: ...
  def kill(self) -> None: ...
  def __enter__(self) -> 'Popen': ...
  def __exit__(self, type, value, traceback) -> bool: ...

# Windows-only: STARTUPINFO etc.

STD_INPUT_HANDLE = ... # type: Any
STD_OUTPUT_HANDLE = ... # type: Any
STD_ERROR_HANDLE = ... # type: Any
SW_HIDE = ... # type: Any
STARTF_USESTDHANDLES = ... # type: Any
STARTF_USESHOWWINDOW = ... # type: Any
CREATE_NEW_CONSOLE = ... # type: Any
CREATE_NEW_PROCESS_GROUP = ... # type: Any