Hide CMD call window

[tester_V]

Greetings!
Running my script every hour on a windows machine.
The script has a “arp-a” cmd call and a window pops up that is very annoying .
How I can suppress the pop up window?
code:

with open(fl,'w') as e :
    cmd = "arp -a"
    returned_output = subprocess.check_output(cmd)
    ln = returned_output.decode("utf-8")
    ln=ln.strip()
    print(ln)
    e.write(ln)

Thank you.

[Gribouillis]

Is it the same if you use

cmd = ['arp', '-a']

[snippsat]

When i test your code no cmd window pop up.
This correct and normal behavior,what are you using to schedule code every hour?
If you run code from command line python arp_code.py,dos still cmd window pop up?

Can also change to this,same no cmd window shall pop up.

import subprocess

with open('arp.txt', 'w') as fp:
    output = subprocess.run(['arp', '-a'], encoding='utf-8', capture_output=True)
    #print(output.stdout.strip())
    fp.write(output.stdout.strip())

[DeaD_EyE]

windows ...

import subprocess


def arp():
    """
    Run arp -a and return the stripped output.
    Window creation is prevented.
    """
    flags = subprocess.CREATE_NO_WINDOW
    
    return subprocess.run(
        ["arp", "-a"],
        capture_output=True,
        encoding="utf8",
        creationflags=flags,
    ).stdout.strip()

[tester_V]

Yes, DOS window was popping up very hour, I understand it was running " arp -a".
Outstanding! It is what I wanted/needed.
You guys (girls?) are great!
Thank you!

[tester_V]

I was happy too early
it still pops up.
I'm not sure how to incorporate "Dead_YEY" snippet correctly to the code I have.
I tried to modify it but it does not work:

import subprocess
from subprocess import CREATE_NO_WINDOW    
flags = subprocess.CREATE_NO_WINDOW
with open('C:\\somedir\\ARP_A.txt','w') as e :
    output = subprocess.run(['arp', '-a'], encoding='utf-8', capture_output=True)
    creationflags=flags    
    output.write(output.stdout.strip())

[deanhystad]

creation_flags=flags doesn't do anything in your code because you put it in the wrong place.. This runs fine for me. No window popping up on windows 10.

import subprocess

print(
    subprocess.run(
        ["arp", "-a"],
        encoding="utf-8",
        capture_output=True,
        creationflags=subprocess.CREATE_NO_WINDOW,   # Notice this is a function argument, not variable assignment
    )
)

[tester_V]

it works, no pop ups!
deanhystad, you are DA MAN!

Thank you!

[deanhystad]

Dead EYE is da man. You need to develop a more critical eye so you can spot your own coding errors.