subprocess：删除Windows中的子进程

Question

在Windows上， subprocess.Popen.terminate调用win32的TerminalProcess 。 但是，我看到的行为是我尝试终止的进程的子进程仍在运行。 这是为什么？ 如何确保进程启动的所有子进程都被终止？

Answer 1

通过使用psutil ：

import psutil, os

def kill_proc_tree(pid, including_parent=True):    
    parent = psutil.Process(pid)
    children = parent.children(recursive=True)
    for child in children:
        child.kill()
    gone, still_alive = psutil.wait_procs(children, timeout=5)
    if including_parent:
        parent.kill()
        parent.wait(5)

me = os.getpid()
kill_proc_tree(me)

Answer 2

将taskkill与/T标志一起使用

p = subprocess.Popen(...)
<wait>
subprocess.call(['taskkill', '/F', '/T', '/PID', str(p.pid)])

taskkill的标志有以下文档：

TASKKILL [/S system [/U username [/P [password]]]]
         { [/FI filter] [/PID processid | /IM imagename] } [/T] [/F]

/S    system           Specifies the remote system to connect to.
/U    [domain\]user    Specifies the user context under which the
                       command should execute.
/P    [password]       Specifies the password for the given user
                       context. Prompts for input if omitted.
/FI   filter           Applies a filter to select a set of tasks.
                       Allows "*" to be used. ex. imagename eq acme*
/PID  processid        Specifies the PID of the process to be terminated.
                       Use TaskList to get the PID.
/IM   imagename        Specifies the image name of the process
                       to be terminated. Wildcard '*' can be used
                       to specify all tasks or image names.
/T                     Terminates the specified process and any
                       child processes which were started by it.
/F                     Specifies to forcefully terminate the process(es).
/?                     Displays this help message.

或者使用comtypes和win32api遍历进程树：

def killsubprocesses(parent_pid):
    '''kill parent and all subprocess using COM/WMI and the win32api'''

    log = logging.getLogger('killprocesses')

    try:
        import comtypes.client
    except ImportError:
        log.debug("comtypes not present, not killing subprocesses")
        return

    logging.getLogger('comtypes').setLevel(logging.INFO)

    log.debug('Querying process tree...')

    # get pid and subprocess pids for all alive processes
    WMI = comtypes.client.CoGetObject('winmgmts:')
    processes = WMI.InstancesOf('Win32_Process')
    subprocess_pids = {} # parent pid -> list of child pids

    for process in processes:
        pid = process.Properties_('ProcessID').Value
        parent = process.Properties_('ParentProcessId').Value
        log.trace("process %i's parent is: %s" % (pid, parent))
        subprocess_pids.setdefault(parent, []).append(pid)
        subprocess_pids.setdefault(pid, [])

    # find which we need to kill
    log.debug('Determining subprocesses for pid %i...' % parent_pid)

    processes_to_kill = []
    parent_processes = [parent_pid]
    while parent_processes:
        current_pid = parent_processes.pop()
        subps = subprocess_pids[current_pid]
        log.debug("process %i children are: %s" % (current_pid, subps))
        parent_processes.extend(subps)
        processes_to_kill.extend(subps)

    # kill the subprocess tree
    if processes_to_kill:
        log.info('Process pid %i spawned %i subprocesses, terminating them...' % 
            (parent_pid, len(processes_to_kill)))
    else:
        log.debug('Process pid %i had no subprocesses.' % parent_pid)

    import ctypes
    kernel32 = ctypes.windll.kernel32
    for pid in processes_to_kill:
        hProcess = kernel32.OpenProcess(PROCESS_TERMINATE, FALSE, pid)
        if not hProcess:
            log.warning('Unable to open process pid %i for termination' % pid)
        else:
            log.debug('Terminating pid %i' % pid)                        
            kernel32.TerminateProcess(hProcess, 3)
            kernel32.CloseHandle(hProcess)

Answer 3

这是Job对象方法的示例代码，但它不使用subprocess win32api.CreateProcess ，而是使用win32api.CreateProcess

import win32process
import win32job
startup = win32process.STARTUPINFO()
(hProcess, hThread, processId, threadId) = win32process.CreateProcess(None, command, None, None, True, win32process.CREATE_BREAKAWAY_FROM_JOB, None, None, startup)

hJob = win32job.CreateJobObject(None, '')
extended_info = win32job.QueryInformationJobObject(hJob, win32job.JobObjectExtendedLimitInformation)
extended_info['BasicLimitInformation']['LimitFlags'] = win32job.JOB_OBJECT_LIMIT_KILL_ON_JOB_CLOSE
win32job.SetInformationJobObject(hJob, win32job.JobObjectExtendedLimitInformation, extended_info)
win32job.AssignProcessToJobObject(hJob, hProcess)

Answer 4

这是一件很难的事情。 Windows实际上并不在进程空间中存储进程树。 也不可能终止一个过程并指定它的孩子也应该死。

解决这个问题的一种方法是使用taskkill并告诉它整个树。

另一种方法（假设你正在产生顶级进程）是使用一个开发时考虑到这种事情的模块： http ： //benjamin.smedbergs.us/blog/tag/killableprocess/

为了自己这样做，你必须花一些时间向后构建列表。 也就是说，进程存储指向它的父节点的指针，但父节点似乎不存储有关子节点的信息。

所以你必须查看系统中的所有进程（实际上并不那么难），然后通过查看父进程字段手动连接点。 然后，您选择您感兴趣的树并遍历整个事物，依次逐个查杀每个节点。

请注意，当父项死亡时，Windows不会更新子项的父指针，因此树中可能存在间隙。 我不知道你能做些什么。

Answer 5

将孩子放在NT Job对象中 ，然后你可以杀死所有孩子

Answer 6

我有同样的问题，只是通过Windows命令杀死进程与杀死孩子的选项“/ T”

def kill_command_windows(pid):
    '''Run command via subprocess'''
    dev_null = open(os.devnull, 'w')
    command = ['TASKKILL', '/F', '/T', '/PID', str(pid)]
    proc = subprocess.Popen(command, stdin=dev_null, stdout=sys.stdout, stderr=sys.stderr)

Answer 7

我用凯文-史密斯的回答创建一个下拉更换为subprocess.Popen该地限制在一个匿名的工作对象，建立了密切的终止在创建子进程：

# coding: utf-8

from subprocess import Popen
import subprocess
import win32job
import win32process
import win32api


class JobPopen(Popen):
    """Start a process in a new Win32 job object.

    This `subprocess.Popen` subclass takes the same arguments as Popen and
    behaves the same way. In addition to that, created processes will be
    assigned to a new anonymous Win32 job object on startup, which will
    guarantee that the processes will be terminated by the OS as soon as
    either the Popen object, job object handle or parent Python process are
    closed.
    """

    class _winapijobhandler(object):
        """Patches the native CreateProcess function in the subprocess module
        to assign created threads to the given job"""

        def __init__(self, oldapi, job):
            self._oldapi = oldapi
            self._job = job

        def __getattr__(self, key):
            if key != "CreateProcess":
                return getattr(self._oldapi, key)  # Any other function is run as before
            else:
                return self.CreateProcess  # CreateProcess will call the function below

        def CreateProcess(self, *args, **kwargs):
            hp, ht, pid, tid = self._oldapi.CreateProcess(*args, **kwargs)
            win32job.AssignProcessToJobObject(self._job, hp)
            win32process.ResumeThread(ht)
            return hp, ht, pid, tid

    def __init__(self, *args, **kwargs):
        """Start a new process using an anonymous job object. Takes the same arguments as Popen"""

        # Create a new job object
        self._win32_job = self._create_job_object()

        # Temporarily patch the subprocess creation logic to assign created
        # processes to the new job, then resume execution normally.
        CREATE_SUSPENDED = 0x00000004
        kwargs.setdefault("creationflags", 0)
        kwargs["creationflags"] |= CREATE_SUSPENDED
        try:
            _winapi = subprocess._winapi  # Python 3
            _winapi_key = "_winapi"
        except AttributeError:
            _winapi = subprocess._subprocess  # Python 2
            _winapi_key = "_subprocess"
        try:
            setattr(subprocess, _winapi_key, JobPopen._winapijobhandler(_winapi, self._win32_job))
            super(JobPopen, self).__init__(*args, **kwargs)
        finally:
            setattr(subprocess, _winapi_key, _winapi)

    def _create_job_object(self):
        """Create a new anonymous job object"""
        hjob = win32job.CreateJobObject(None, "")
        extended_info = win32job.QueryInformationJobObject(hjob, win32job.JobObjectExtendedLimitInformation)
        extended_info['BasicLimitInformation']['LimitFlags'] = win32job.JOB_OBJECT_LIMIT_KILL_ON_JOB_CLOSE
        win32job.SetInformationJobObject(hjob, win32job.JobObjectExtendedLimitInformation, extended_info)
        return hjob

    def _close_job_object(self, hjob):
        """Close the handle to a job object, terminating all processes inside it"""
        if self._win32_job:
            win32api.CloseHandle(self._win32_job)
            self._win32_job = None

    # This ensures that no remaining subprocesses are found when the process
    # exits from a `with JobPopen(...)` block.
    def __exit__(self, exc_type, value, traceback):
        super(JobPopen, self).__exit__(exc_type, value, traceback)
        self._close_job_object(self._win32_job)

    # Python does not keep a reference outside of the parent class when the
    # interpreter exits, which is why we keep it here.
    _Popen = subprocess.Popen  
    def __del__(self):
        self._Popen.__del__(self)
        self._close_job_object(self._win32_job)