Python 3 Programming Tutorial - Subprocess module

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[JV-jcci]

Wow this saved my (brain) life! The best tutorial after countless hours of trying to understand subprocess. Even my paid online course couldn't have done a better job. Thank you so much! You have a new subscriber.

[alexp]

I have recently started with Python and have been reading and watching videos. This is by far the best and easiest to understand explanation and I now understand it. Thank you!

[lalu]

Very helpful indeed. I've used this info to create 2 simple executable scripts on my Linux VPS. These scripts use sudo chown to change the owner of the 'wp-content' folder to 'www-data' in order to be able to update Worpress from the dashboard. Then I use the second script to change back the owner to my user name. Thanks for all your efforts Harrison, I very much enjoy this series and the one on Pandas.

[jonathanbrooks]

Hi there, I'm not sure whether you're aware or not, but if you put: universal_newlines=True within subprocess.check_output(), or most of the other functions within subprocess, then instead of receiving a binary stream, it is interpreted with new lines, so that stdout will look just as pretty as in the shell.

[jeffg]

Great video. Gotta appreciate tutorials that show germane examples and explain in terms you can grasp.

[meltedcheese]

I like how you showed how to do both versions, great video man!

[kylewood]

a little advice: never use shell=True unless you really have to call the command through shell, and this video does not talk about exception handling such as zombie command running forever

[Pterryreal]

The subprocess call will be shown in pycharm and sublime tex how it should be. Maybe the IDE you mentioned was an exception ;)

[comicks]

i just found the most underrated channel on youtube.

[chunchunmaru]

On the subprocess.check_output wouldn't you just decode the output?


output = subprocess.check_output('ls', shell=True)
print(output.decode("utf-8"))


This will turn it into a string that would print the \n characters as new lines, giving you clean output

[FreeER]

You don't need replaces to fix the output @5:08(unless you meant using a regex to pull data out of the result which is different, you did say 'parse' but I'll comment anyways since it's some extra information for other people and info is _nearly_ always good right?).
ex:
output = b'Hello\r\n'
print(output) # gives b'hello\r\n' in 3.x, the expected 'hello'+newline in 2.x
print(output.decode('ascii')) # gives the desired 'hello'+newline in 3.x and 2.x
print(output.decode('utf-8')) # also gives the desired 'hello'+newline in 3.x and 2.x

@11:30 you mention you think 'r is for return and n for newline'. Actually 'r' is for carriage return (so, close) and 'n' is for 'line feed', which are old terms carried over from typewriters, a 'carriage return' would return the carriage (the part that held and moved the paper as you typed) back to the beginning of the line and a 'line feed' would advance ('feed') the paper one 'line' down. Thus you'd be at the start of a new line ready to continue typing.

[GonsalvoDeCordova]

Around 10:00 when you are flailing a bit, I think you could have done \' to escape those single quotes.  Of course your final workaround was a better idea.

[zbzb-icsr]

Please make a tutorial on pipes thanks!

[kapil-pjld]

all your videos are awesome while I want to know about the piping so please upload the video on it and also changing windows directory using popen

[fredyharter]

Hey Harrison! I am looking for a good example code using sys and subprocess modules to communicate between python and non-python programs. I don't know any other programming language, but I feel like these two modules can open the door to other languages so I want to dig into examples and see how other programming languages allow to do that.
Where do good examples hide on the net? :)

[alexcohen]

the fix to where your using subprocess to call systut.py would probably be:
subprocess.call("python systut.py \"check this out\" ", shell=true)

[ashketchum]

If you already made a video-tutorial on PIPEs, please post a link here.

[armanavetisyan]

How can I use login credentials??? I'm trying connect to linux from Windows... pexpect doesn't work for windows... So I can use only Subprocess.. Pls show me example how can I use login credentials.. Thanks..

[suryameda]

Can we terminate a process that is running in terminal using python, just quit the process and not totally killing the command prompt itself?

[akeemlouigarde]

Im using python 3.7.0 and "Check this out!" is not printing. It only shows me 0.