How can os.popen take argument externaly to run another script

Question

I am trying to write a python CLI program using module python cmd. When I try to execute another python script in my CLI program my objective is I have some python script in other folder and CLI program in other folder. I am trying to execute those python script using CLI program.

Below is the os.popen method used to execute other script there is CLI program:

import cmd
import os
import sys

class demo(cmd.Cmd):

   def do_shell(self,line,args):
     """hare is function to execute the other script"""
    output = os.popen('xterm -hold -e python %s' % args).read()
    output(sys.argv[1])

def do_quit(self,line):

    return True

if __name__ == '__main__':
    demo().cmdloop()

and hare is error:

(Cmd) shell demo-test.py
Traceback (most recent call last):
File "bemo.py", line 18, in <module>
demo().cmdloop()
File "/usr/lib/python2.7/cmd.py", line 142, in cmdloop
stop = self.onecmd(line)
File "/usr/lib/python2.7/cmd.py", line 221, in onecmd
return func(arg)
TypeError: do_shell() takes exactly 3 arguments (2 given)

there is some link to other cmd CLI program 1 = cmd – Create line-oriented command processors 2 = Console built with Cmd object (Python recipe)

and some screen shot's for more information:

Please run above code in your system.

if anyone can have idea. how to solve this please post your program..it is very help for my work — Najeeb Choudhary, Oct 04 '15 at 19:34
to execute other script,and i also already try sys.system() if you have idea to solve this with os.system() please post it... — Najeeb Choudhary, Oct 04 '15 at 19:41
ok sorry for import sys i am remove this when is post my program. — Najeeb Choudhary, Oct 04 '15 at 19:43
yep and execute python script in new xterm...can you help me — Najeeb Choudhary, Oct 04 '15 at 20:04

idjaw · Accepted Answer · 2015-10-04T20:13:18.340

1

As specified in the doc:

https://pymotw.com/2/cmd/index.html

do_shell is defined as such:

do_shell(self, args):

But you are defining it as

do_shell(self, line, args):

I think the intended use is define it as specified from the documentation.

I ran your code and followed your example. I replicated your error. I then, as specified in the documentation for do_shell, I changed the method to the as expected:

do_shell(self, args):

From there, the sys module was missing, so you need to import that as well (unless you did not copy it from your source). After that, I got an error for index out of range, probably because of the expectation of extra parameters needing to be passed.

Furthermore, because you are talking about Python scripts, I don't see the need for the extra commands you are adding, I simply changed the line to this:

output = os.popen('python %s' % args).read()

However, if there is a particular reason you need the xterm command, then you can probably put that back and it will work for your particular case.

I also, did not see the use case for this:

output(sys.argv[1])

I commented that out. I ran your code, and everything worked. I created a test file that just did a simple print and it ran successfully.

So, the code actually looks like this:

def do_shell(self, args):
    """hare is function to execute the other script"""
    output = os.popen('python %s' % args).read()
    print output

The full code should look like this:

import cmd
import os
import sys

class demo(cmd.Cmd):

    def do_shell(self, args):
        """hare is function to execute the other script"""
        output = os.popen('python %s' % args).read()
        print output

    def do_quit(self,line):

        return True

if __name__ == '__main__':
    demo().cmdloop()

edited Oct 04 '15 at 20:13

answered Oct 04 '15 at 19:35

idjaw

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read document properly. do_shell(self,line,args): here args for argument. – Najeeb Choudhary Oct 04 '15 at 19:37
Is this link the correct doc you are referencing: https://pymotw.com/2/cmd/index.html – idjaw Oct 04 '15 at 19:38
i post on link in my quastion – Najeeb Choudhary Oct 04 '15 at 19:38
@NajeebChoudhary Let me know what you think. I updated my answer – idjaw Oct 04 '15 at 19:49
Your indentation is off. Make sure all your spaces are properly aligned. Don't mix tabs/spaces. – idjaw Oct 04 '15 at 19:54
your program not work,,try on your system,,,this error come my system """""najeeb@najeeb:~/Desktop/project$ python test.py File "test.py", line 11 output = os.popen('python %s' % args).read() ^ IndentationError: unindent does not match any outer indentation level"""""" – Najeeb Choudhary Oct 04 '15 at 19:55
An indentation error does not mean my code is broken. It means that you have not lined up your code properly to where it has to go. – idjaw Oct 04 '15 at 19:57
no this for =''''line 11 output = os.popen('python %s' % args).read() ''' this line...please upload full script – Najeeb Choudhary Oct 04 '15 at 20:11
I've put the code I used. I have this working on my end. This is exactly what I am using and it works. – idjaw Oct 04 '15 at 20:13
i need your one more fevour...how can i Auto-Completion function add,,in this program, – Najeeb Choudhary Oct 04 '15 at 20:18
I think this should help you: http://stackoverflow.com/questions/4001708/change-how-python-cmd-module-handles-autocompletion – idjaw Oct 04 '15 at 20:24
I personally have not had experience with this. So that is the extent of my knowledge with that. – idjaw Oct 04 '15 at 20:24

How can os.popen take argument externaly to run another script

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