Show terminal output in a gui window using python Gtk

Question

I am developing a program, in which I want a window that will display the output thrown by the terminal (like a package manager does ). For example, if I give the install command, the installation process should be outptutted to my window and not the terminal. Is there a way to do this in python Gtk?

I am using an Ubuntu 13.04.

Answer 1

If you are on Linux (as you state), something like this should work:

import gtk 
import gobject
import pango
import os
from subprocess import Popen, PIPE
import fcntl

wnd = gtk.Window()
wnd.set_default_size(400, 400)
wnd.connect("destroy", gtk.main_quit)
textview = gtk.TextView()
fontdesc = pango.FontDescription("monospace")
textview.modify_font(fontdesc)
scroll = gtk.ScrolledWindow()
scroll.add(textview)
exp = gtk.Expander("Details")
exp.add(scroll)
wnd.add(exp)
wnd.show_all()
sub_proc = Popen("ping -c 10 localhost", stdout=PIPE, shell=True)
sub_outp = ""


def non_block_read(output):
    fd = output.fileno()
    fl = fcntl.fcntl(fd, fcntl.F_GETFL)
    fcntl.fcntl(fd, fcntl.F_SETFL, fl | os.O_NONBLOCK)
    try:
        return output.read().decode("utf-8")
    except:
        return ''


def update_terminal():
    textview.get_buffer().insert_at_cursor(non_block_read(sub_proc.stdout))
    return sub_proc.poll() is None

gobject.timeout_add(100, update_terminal)
gtk.main()

The nonblocking read idea is from here.

Using a Label to display the text:

import gtk 
import gobject
import os
from subprocess import Popen, PIPE
import fcntl

wnd = gtk.Window()
wnd.set_default_size(400, 400)
wnd.connect("destroy", gtk.main_quit)
label = gtk.Label()
label.set_alignment(0, 0)
wnd.add(label)
wnd.show_all()
sub_proc = Popen("ping -c 10 localhost", stdout=PIPE, shell=True)
sub_outp = ""


def non_block_read(output):
    ''' even in a thread, a normal read with block until the buffer is full '''
    fd = output.fileno()
    fl = fcntl.fcntl(fd, fcntl.F_GETFL)
    fcntl.fcntl(fd, fcntl.F_SETFL, fl | os.O_NONBLOCK)
    try:
        return output.read().decode("utf-8")
    except:
        return ''


def update_terminal():
    label.set_text(label.get_text() + non_block_read(sub_proc.stdout))
    return sub_proc.poll() is None

gobject.timeout_add(100, update_terminal)
gtk.main()