Steps to use Python to open the CMD window: 1. Import the subprocess module; 2. Create a subprocess object, specify command parameters, and redirect the output; 3. Get the subprocess output; 4. Decode the output (optional).
Open the CMD command window with Python
The steps to open the Windows CMD command window using Python are as follows:
1. Import the subprocess module
First, you need to import Python's subprocess module, which is used to create and manage subprocesses.
import subprocess
2. Create subprocess object
Create a subprocess object to represent the CMD process. You can use the subprocess.Popen()
function and specify the following arguments:
-
args
: The command to run (in this case'cmd'
). -
stdout
: Specifies the file object to which the subprocess's standard output stream is redirected (in this casesubprocess.PIPE
, which creates a pipe object , so that Python can read the output of the child process in the parent process). -
stderr
: Specifies the file object to which the subprocess's standard error stream is to be redirected (alsosubprocess.PIPE
in this case).
process = subprocess.Popen(['cmd'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
3. Get the subprocess output
Use the subprocess.communicate()
function to get the standard output and error output of the subprocess . This function will block the parent process until the child process completes execution.
stdout, stderr = process.communicate()
4. Decode output (optional)
The subprocess module returns the output of the subprocess as a byte stream. If you need to process text output, you need to use the decode()
function to decode it into text.
stdout_text = stdout.decode('utf-8') stderr_text = stderr.decode('utf-8')
Full example:
import subprocess process = subprocess.Popen(['cmd'], stdout=subprocess.PIPE, stderr=subprocess.PIPE) stdout, stderr = process.communicate() stdout_text = stdout.decode('utf-8') stderr_text = stderr.decode('utf-8') print('stdout:', stdout_text) print('stderr:', stderr_text)
Now you can open the CMD command window and access its output through a Python script.
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