Write to terminal in Tkinter GUI

Question

I am trying to show the changes in the command line in real time in my Tkinter GUI, I managed to create the GUI and integrate the terminal into it, but I cant bind the buttons with the terminal, my code is :

import Tkinter
from Tkinter import *
import subprocess
import os
from os import system as cmd

WINDOW_SIZE = "600x400"
top = Tkinter.Tk()
top.geometry(WINDOW_SIZE)

def helloCallBack():
   print "Below is the output from the shell script in terminal"
   subprocess.call('perl /projects/tfs/users/$USER/scripts_coverage.pl', shell=True)
def BasicCovTests():
   print "Below is the output from the shell script in terminal"
   subprocess.call('perl /projects/tfs/users/$USER/basic_coverage_tests.pl', shell=True)
def FullCovTests():
   print "Below is the output from the shell script in terminal"
   subprocess.call('perl /projects/tfs/users/$USER/basic_coverage_tests.pl', shell=True)


Scripts_coverage  = Tkinter.Button(top, text ="Scripts Coverage", command = helloCallBack)
Scripts_coverage.pack()

Basic_coverage_tests  = Tkinter.Button(top, text ="Basic Coverage Tests", command = BasicCovTests)
Basic_coverage_tests.pack()

Full_coverage_tests  = Tkinter.Button(top, text ="Full Coverage Tests", command = FullCovTests)
Full_coverage_tests.pack()

termf = Frame(top, height=100, width=500)

termf.pack(fill=BOTH, expand=YES)
wid = termf.winfo_id()

os.system('xterm -into %d -geometry 100x20 -sb &' % wid)

def send_entry_to_terminal(*args):
    """*args needed since callback may be called from no arg (button)
   or one arg (entry)
   """
    cmd("%s" % (BasicCovTests))

top.mainloop()

#

I want win I click the button to see it printing the command in the terminal

Answer 1

Well you are in the right module at least. subprocess also contains utilities for viewing the output of the command that you run, so that you can have the output of your perl script made available to you.

If you want to simply get all of the subprocesses output after it finishes running, use subrocess.check_output() . It should be more than sufficient.

However, if the subtask is a long running program or you require monitoring in real-time, you should really look at the Popen class in the subprocess module. You can create and monitor a new process like this:

import subprocess

p = subprocess.Popen("perl /projects/tfs/users/$USER/scripts_coverage.pl", stdout = subprocess.PIPE, stderr = subprocess.STDOUT, shell = True)   

while True:
    line = p.stdout.readline()
    print line
    if not line: break

From there you could echo the output into a terminal or use a Tkinter widget to display the rolling program output. Hope this helps.