Python gobject和subprocess.Popen在GTK GUI中通信

Python gobject和subprocess.Popen在GTK GUI中通信,python,pygtk,multiprocessing,popen,gobject,Python,Pygtk,Multiprocessing,Popen,Gobject,我试图使用一个gobject来允许Popen进程和gtkgui之间的通信 受此启发: 我实现了类似的功能: 但是我注意到gobject即使在Popen进程终止后也会占用大量的CPU周期。只需运行上面的脚本并观看Ubuntu系统监视器 在与“pty”合作后,我提出了以下建议: import gtk,pygtk import subprocess import gobject import pty, os, time class CommandTextView(gtk.TextView):

我试图使用一个gobject来允许Popen进程和gtkgui之间的通信

受此启发:

我实现了类似的功能:

但是我注意到gobject即使在Popen进程终止后也会占用大量的CPU周期。只需运行上面的脚本并观看Ubuntu系统监视器

在与“pty”合作后,我提出了以下建议:

import gtk,pygtk
import subprocess
import gobject
import pty, os, time

class CommandTextView(gtk.TextView):
    def __init__(self):
        super(CommandTextView,self).__init__()
        self.master, self.slave = pty.openpty()
        gobject.io_add_watch(os.fdopen(self.master), gobject.IO_IN, self.write_to_buffer)
        self.proc = None

    def run(self, w, cmd):
        if self.proc == None or self.proc.poll() != None: # poll()=None means still running
            self.proc = subprocess.Popen(cmd.split(), shell=True, stdout=self.slave, stderr=self.slave)

    def stop(self,w):
        if type(self.proc) is subprocess.Popen:
            self.proc.kill()
            while self.proc.poll() == None:
                time.sleep(0.1)
            self.proc = None

    def write_to_buffer(self, fd, condition):
        if condition == gobject.IO_IN:
            char = fd.readline()
            print 'adding:',char    
            buf = self.get_buffer()
            buf.insert_at_cursor(char)
            return True
        else:
            return False

def test():
    win=gtk.Window()
    vbox = gtk.VBox(False, 0)
    win.set_size_request(300,300)
    win.connect('delete-event',lambda w,e : gtk.main_quit())
    ctv=CommandTextView()
    bt1 = gtk.Button('Run')
    bt2 = gtk.Button('Stop')
    vbox.pack_start(ctv)
    vbox.pack_end(bt2,False,False)
    vbox.pack_end(bt1,False,False)
    win.add(vbox)

    bt1.connect("clicked", ctv.run, 'ls -la')
    bt2.connect("clicked", ctv.stop)
    win.show_all()
    gtk.main()

if __name__=='__main__': test()
我的问题是:

  • pty是个好主意吗?它也可以用于Windows吗

  • 有没有可能避免使用pty而只使用stdout而不存在高CPU使用率的问题

  • 如果您第一次运行此脚本,它似乎会缓冲txt输出并给出不完整的输出


感谢您的帮助

将无缓冲读取与操作系统一起使用。读取,它需要实际的文件描述符。您的fd不是一个真正的文件描述符,它是一个文件对象;通常称为f


如果你想确定这个过程是死的,请使用os.kill。

这是为那些在2016年之后偶然看到这篇文章并试图将其改写为Gtk3的人准备的

#!/usr/bin/env python3

import gi
gi.require_version('Gtk', '3.0')

from gi.repository import Gtk
from gi.repository import GObject

import os
import fcntl
import subprocess

def unblock_fd(stream):
    fd = stream.fileno()
    fl = fcntl.fcntl(fd, fcntl.F_GETFL)
    fcntl.fcntl(fd, fcntl.F_SETFL, fl | os.O_NONBLOCK)


class StreamTextBuffer(Gtk.TextBuffer):
    '''TextBuffer read command output syncronously'''
    def __init__(self):
        Gtk.TextBuffer.__init__(self)
        self.IO_WATCH_ID = tuple()


    def bind_subprocess(self, proc):
        unblock_fd(proc.stdout)
        watch_id_stdout = GObject.io_add_watch(
            channel   = proc.stdout,
            priority_ = GObject.IO_IN,
            condition = self.buffer_update,
            # func      = lambda *a: print("func") # when the condition is satisfied
            # user_data = # user data to pass to func
        )

        unblock_fd(proc.stderr)
        watch_id_stderr = GObject.io_add_watch(
            channel   = proc.stderr,
            priority_ = GObject.IO_IN,
            condition = self.buffer_update,
            # func      = lambda *a: print("func") # when the condition is satisfied
            # user_data = # user data to pass to func
        )

        self.IO_WATCH_ID = (watch_id_stdout, watch_id_stderr)
        return self.IO_WATCH_ID


    def buffer_update(self, stream, condition):
        self.insert_at_cursor(stream.read())
        return True # otherwise isn't recalled


def sample():
    root = Gtk.Window()
    root.set_default_size(400, 260)
    root.connect("destroy", Gtk.main_quit)
    root.connect( # quit when Esc is pressed
        'key_release_event',
        lambda w, e: Gtk.main_quit() if e.keyval == 65307 else None
    )
    layout = Gtk.Box(orientation=1)
    scroll = Gtk.ScrolledWindow()
    layout.pack_start(scroll, expand=1, fill=1, padding=0)

    buff = StreamTextBuffer()
    textview = Gtk.TextView.new_with_buffer(buff)
    scroll.add(textview)

    button_start = Gtk.Button("Execute Command")
    layout.add(button_start)

    def on_click(widget):
        if len(buff.IO_WATCH_ID):
            for id_ in buff.IO_WATCH_ID:
                # remove subprocess io_watch if not removed will
                # creates lots of cpu cycles, when process dies
                GObject.source_remove(id_)
            buff.IO_WATCH_ID = tuple()
            on_click.proc.terminate() # send SIGTERM
            widget.set_label("Execute Command")
            return

        on_click.proc = subprocess.Popen(
            [ 'ping', '-c', '3', 'localhost' ],
            stdout = subprocess.PIPE,
            stderr = subprocess.PIPE,
            universal_newlines=True,
        )
        buff.bind_subprocess(on_click.proc)
        widget.set_label("STOP!")

    button_start.connect("clicked", on_click)
    root.add(layout)
    root.show_all()


if __name__ == "__main__":
    sample()
    Gtk.main()

请你再详细说明一下解决办法是什么好吗?实际上,我怀疑self.proc.kill()命令实际上并没有终止进程,因为我使用了shell=True。可能吗?例如,如果cmd='ls-R/',这个例子似乎不起作用。为了使它工作,您可能需要shell=False,在这种情况下,停止按钮将不工作。总之,这不是pygtk进程gui通信的一个很好的例子。