问题

我有这段代码，这是我想象力和ChatGPT帮助的产物：

import subprocess
import threading
import tkinter as tk

class PingThread(threading.Thread):
    def __init__(self, text_widget):
        super().__init__()
        self.text_widget = text_widget
        self.process = None
        self.stop_event = threading.Event()

    def run(self):
        self.process = subprocess.Popen(['cmd'], stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE, shell=True)
        self.process.stdin.write(b'ping -t google.com\n')
        self.process.stdin.flush()

        while not self.stop_event.is_set():
            line = self.process.stdout.readline().decode('cp866')
            if not line:
                break
            self.text_widget.insert(tk.END, line)
            self.text_widget.see(tk.END)

    def stop(self):
        if self.process:
            self.process.communicate(b'\x03')
            self.process.wait()
        self.stop_event.set()

def ping():
    ping_thread = PingThread(text)
    ping_thread.start()

    def handle_ctrl_c(event):
        ping_thread.stop()
        text.insert(tk.END, '\nProcess terminated.\n')

    root.bind('<Control-c>', handle_ctrl_c)

root = tk.Tk()

text = tk.Text(root)
text.pack()

button = tk.Button(root, text='Ping', command=ping)
button.pack()

root.mainloop()

我正在尝试在Tkinter中创建一个控制台模拟。我发送ping请求并监听控制台以获取其响应。一切都运行正常，除了Ctrl+C命令，它应该结束ping执行并从控制台返回统计信息。当我尝试发送self.process.communicate(b'\x03')时，窗口会冻结。这是什么原因？据我了解，这一行应该发送Ctrl+C到控制台，并且while循环应该接收来自控制台的最后几行，包括ping的统计信息。

import subprocess
import threading
import tkinter as tk

class PingThread(threading.Thread):
    def __init__(self, text_widget):
        super().__init__()
        self.text_widget = text_widget
        self.process = None
        self.stop_event = threading.Event()

    def run(self):
        self.process = subprocess.Popen(['cmd'], stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE, shell=True)
        self.process.stdin.write(b'ping -t google.com\n')
        self.process.stdin.flush()

        while not self.stop_event.is_set():
            line = self.process.stdout.readline().decode('cp866')
            if not line:
                break
            self.text_widget.insert(tk.END, line)
            self.text_widget.see(tk.END)

    def stop(self):
        if self.process:
            self.process.communicate(b'\x03')
            self.process.wait()                                #Window freezes on the .communicate line, so this and line below are not executing at all
        self.stop_event.set()

def ping():
    ping_thread = PingThread(text)
    ping_thread.start()

    def handle_ctrl_c(event):
        ping_thread.stop()
        text.insert(tk.END, '\nProcess terminated.\n')

    root.bind('<Control-c>', handle_ctrl_c)

root = tk.Tk()

text = tk.Text(root)
text.pack()

button = tk.Button(root, text='Ping', command=ping)
button.pack()

root.mainloop()

答案1

得分: 1

以下是代码部分的翻译：

So now that I better understand your issue, here is another try. My answer is not working perfectly, because I use a workaround to get the last 4 lines after sending `CTRL_BREAK_EVENT`

然而，现在我更好地理解了您的问题，所以这里有另一次尝试。我的答案并不完美，因为我使用了一种解决方法来在发送 `CTRL_BREAK_EVENT` 后获取最后的 4 行。

However, for your question the 2 most important things:
1) Use `creationflags=subprocess.CREATE_NEW_PROCESS_GROUP` when you create your process. If I understand it correctly, this creates a different process for the terminal and the ping command, so you can still get the output from the terminal after passing the stop signal.
2) To terminate the `ping` command, send `signal.CTRL_BREAK_EVENT` on Windows. In general, these signals seem to be not consistent for operating systems. (see also the comment from @chris_se)

然而，对于您的问题，有两个最重要的事项：
1) 在创建进程时使用 `creationflags=subprocess.CREATE_NEW_PROCESS_GROUP`。如果我理解正确，这将为终端和 ping 命令创建不同的进程，因此在传递停止信号后，您仍然可以获取终端的输出。
2) 要终止 `ping` 命令，请在 Windows 上发送 `signal.CTRL_BREAK_EVENT`。一般来说，这些信号在不同操作系统上可能不一致。（也请参考 @chris_se 的评论）

The workaround I use is, to only read the next 4 lines of `STDOUT` after setting the stop event (exiting the while loop). I know that the statistics summary of the `ping` command will print this number of lines. Of course we could increase it to be sure to not miss anything.

我使用的解决方法是，在设置停止事件后（退出 while 循环）仅读取 `STDOUT` 的下一行 4 行。我知道 `ping` 命令的统计摘要会打印这些行数。当然，我们可以增加这个数字以确保不会错过任何内容。

Here is the code:

以下是代码部分的翻译：

```python
import subprocess
import threading
import tkinter as tk
import signal

import subprocess
import threading
import tkinter as tk
import signal

class PingThread(threading.Thread):
    def __init__(self, text_widget):
        super().__init__()
        self.text_widget = text_widget
        self.process = None
        self.stop_event = threading.Event()

    def run(self):
        self.process = subprocess.Popen(['cmd'], stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, creationflags=subprocess.CREATE_NEW_PROCESS_GROUP)
        self.process.stdin.write(b'ping -t google.com\n')
        self.process.stdin.flush()

        while not self.stop_event.is_set():
            line = self.process.stdout.readline().decode('cp866')
            if not line:
                break
            self.text_widget.insert(tk.END, line)
            self.text_widget.see(tk.END)

        self.text_widget.insert(tk.END, self.process.stdout.readline().decode('cp866'))
        for i in range(4):
            self.text_widget.insert(tk.END, self.process.stdout.readline().decode('cp866'))
            self.text_widget.see(tk.END)
            i += 1

        self.process.stdout.close()
        self.process.kill()
        self.text_widget.insert(tk.END, '\nProcess terminated.')
        root.unbind('<Control-c>')

    def stop(self):
        if self.process:
            self.stop_event.set()
            self.process.send_signal(signal.CTRL_BREAK_EVENT)

def ping():
    ping_thread = PingThread(text)
    ping_thread.start()

    def handle_ctrl_c(event):
        ping_thread.stop()

    root.bind('<Control-c>', handle_ctrl_c)

root = tk.Tk()

text = tk.Text(root)
text.pack()

button = tk.Button(root, text='Ping', command=ping)
button.pack()

root.mainloop()

希望这些翻译对您有所帮助。如有任何疑问，请随时提出。

import subprocess
import threading
import tkinter as tk
import signal
class PingThread(threading.Thread):
def __init__(self, text_widget):
super().__init__()
self.text_widget = text_widget
self.process = None
self.stop_event = threading.Event()
def run(self):
self.process = subprocess.Popen(['cmd'], stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, creationflags=subprocess.CREATE_NEW_PROCESS_GROUP)
self.process.stdin.write(b'ping -t google.com\n')
self.process.stdin.flush()
while not self.stop_event.is_set():
line = self.process.stdout.readline().decode('cp866')
if not line:
break
self.text_widget.insert(tk.END, line)
self.text_widget.see(tk.END)
self.text_widget.insert(tk.END, self.process.stdout.readline().decode('cp866'))
for i in range(4):
self.text_widget.insert(tk.END, self.process.stdout.readline().decode('cp866'))
self.text_widget.see(tk.END)
i += 1
self.process.stdout.close()
self.process.kill()
self.text_widget.insert(tk.END, '\nProcess terminated.\n')
root.unbind('<Control-c>')
def stop(self):
if self.process:
self.stop_event.set()
self.process.send_signal(signal.CTRL_BREAK_EVENT)
def ping():
ping_thread = PingThread(text)
ping_thread.start()
def handle_ctrl_c(event):
ping_thread.stop()
root.bind('<Control-c>', handle_ctrl_c)
root = tk.Tk()
text = tk.Text(root)
text.pack()
button = tk.Button(root, text='Ping', command=ping)
button.pack()
root.mainloop()