Python Script Execute Commands in Terminal

Python Script execute commands in Terminal

There are several ways to do this:

A simple way is using the os module:

import os
os.system("ls -l")

More complex things can be achieved with the subprocess module:
for example:

import subprocess
test = subprocess.Popen(["ping","-W","2","-c", "1", "192.168.1.70"], stdout=subprocess.PIPE)
output = test.communicate()[0]

How to run a terminal command inside a python script?

You can try with:

import os
os.system('...your command...')

How do I execute a program or call a system command?

Solution:

Step #1: Add module

Use the subprocess module in the standard library:

import subprocess
subprocess.run(["ls", "-l"])

[This module allows you to spawn new processes, connect to their input/output/error pipes, and obtain their return codes. Read more via: subprocess]

Step #2: Call an external command

The simplest way to call an external command is to use the subprocess.run() function, which runs the specified command and waits for it to complete. Here's the demo code with an output:

import subprocess

result = subprocess.run(["ls"], capture_output=True)
print(result.stdout)

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Advantage:
The advantage of subprocess.run over os.system is that it is more flexible (you can get the stdout, stderr, the "real" status code, better error handling, etc...).

Tip:
The shlex.split() method can be used to break down simple shell commands into individual arguments. But it may not work correctly with longer and more complex commands that include pipe symbols. This can make debugging difficult. To avoid this issue, the shell=True argument can be used, however, this approach has potential security risks.

Another way:
You can also use other functions like subprocess.Popen() to run a command and also redirect the stdout and stderr to a pipe, and you can also redirect the input to the process.

Security implications:
While running external commands, you should be careful to properly escape any arguments that contain special characters, as they might be interpreted by the shell in unexpected ways.

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Learning resources:
Even the documentation for os.system recommends using subprocess instead:

The subprocess module provides more powerful facilities for spawning new processes and retrieving their results; using that module is preferable to using this function. See the Replacing Older Functions with the subprocess Module section in the subprocess documentation for some helpful recipes.

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Note:
On Python 3.4 and earlier, use subprocess.call instead of .run:

subprocess.call(["ls", "-l"])

If using Python 3.5 +, use subprocess.run().

How to execute a command in the terminal from a Python script?

The echo terminal command echoes its arguments, so printing the command to the terminal is the expected result.

Are you typing echo driver.exe bondville.dat and is it running your driver.exe program?

If not, then you need to get rid of the echo in the last line of your code:

os.system(command)

Execute Commands in Kali-Linux's Terminal through Python

Try this:

import subprocess
command = "python3 app.py"
subprocess.call(command, shell=True)

Open a terminal in Python script and execute terminal commands in that newly opened terminal

I don't fully understand the wording of your question, but if you want to pop up a Terminal and run:

ls -l 

in that Terminal, you can do:

import os
os.system("""osascript -e 'tell application "Terminal" to do script "ls -l"'""")

How can I open a terminal, execute a python script on it and then wait for the script to end?

You are chaining commands to run in the local shell using

def function():
    cmd = "gnome-terminal; python3 simple_action_client.py"
    subprocess.check_output(cmd, shell=True)
    print("I'm done!")

You need to adjust the cmd line to tell gnome-terminal to execute the command

def function():
    cmd = "gnome-terminal --wait -- python3 simple_action_client.py"
    subprocess.check_output(cmd, shell=True)
    print("I'm done!")

Notice the "--" instead of the ";" and the "--wait" to wait for the command inside the shell to exit

Python, run terminal, and execute command in it

according to the Python docs, it is recommended that os.system be replaced with the subprocess module .

status = os.system("mycmd" + " myarg")
# becomes
status = subprocess.call("mycmd" + " myarg", shell=True)

How to execute a shell program taking inputs with python?

I'll try and give you some hints to get you started - though bear in mind I do not know any of your tools, i.e. waf or csp-client, but hopefully that will not matter.

I'll number my points so you can refer to the steps easily.

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Point 1

If waf is a build system, I wouldn't keep running that every time you want to run your csp-client. Just use waf to rebuild when you have changed your code - that should save time.

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Point 2

When you change directory to /home/augustin/workspaceGS/gs-sw-nanosoft-product-interface-application-2.5.1 and then run ./build/csp-client you are effectively running:

/home/augustin/workspaceGS/gs-sw-nanosoft-product-interface-application-2.5.1/build/csp-client -k/dev/ttyUSB1

But that is rather annoying, so I would make a symbolic link to that that from /usr/local/bin so that you can run it just with:

csp-client -k/dev/ttyUSB1

So, I would make that symlink with:

ln -s /home/augustin/workspaceGS/gs-sw-nanosoft-product-interface-application-2.5.1/build/csp-client  /usr/local/bin/csp-client

You MAY need to put sudo at the start of that command. Once you have that, you should be able to just run:

csp-client -k/dev/ttyUSB1

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Point 3

Your Python code doesn't work because every os.system() starts a completely new shell, unrelated to the previous line or shell. And the shell that it starts then exits before your next os.system() command.

As a result, the cmp ident command never goes to the csp-client. You really need to send the cmp ident command on the stdin or "standard input" of csp-client. You can do that in Python, it is described here, but it's not all that easy for a beginner.

Instead of that, if you just have aa few limited commands you need to send, such as "take a picture", I would make and test complete bash scripts in the Terminal, till I got them right and then just call those from Python. So, I would make a bash script in your HOME directory called, say csp-snap and put something like this in it:

#/bin/bash

# Extend PATH so we can find "/usr/local/bin/csp-client"
PATH=$PATH:/usr/local/bin

{
   # Tell client to take picture
   echo "nanoncam snap" 
   # Exit csp-client
   echo exit
} | csp-client -k/dev/ttyUSB1

Now make that executable (only necessary once) with:

chmod +x $HOME/csp-snap

And then you can test it with:

$HOME/csp-snap

If that works, you can copy the script to /usr/local/bin with:

cp $HOME/csp-snap /usr/local/bin

You may need sudo at the start again.

Then you should be able to take photos from anywhere just with:

csp-snap

Then your Python code becomes easy:

os.system('/usr/local/bin/csp-snap')

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