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

Question

I want to execute a command in terminal from a Python script.

 ./driver.exe bondville.dat

This command is getting printed in the terminal, but it is failing to execute.

Here are my steps:

echo = "echo"
command="./driver.exe"+" "+"bondville.dat"
os.system(echo + " " + command)

It should execute the command, but it's just printing it on terminal. When feeding the same thing manually it's executing. How do I do this from a script?

Answer 1

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)

Answer 2

You can use the subprocess.check_call module to run the command, you don't need to echo to run the command:

from subprocess import check_call

check_call(["./driver.exe", "bondville.dat"])

Which is equivalent to running ./driver.exe bondville.dat from bash.

If you wanted to get the output you would use check_outout:

from subprocess import check_output

out = check_output(["./driver.exe", "bondville.dat"])

In your own code you are basically echoing the string command not actually running the command i.e echo "./driver.exe bondville.dat" which would output ./driver.exe bondville.dat in your shell.