> On 9 Mar 2022, at 14:42, mangelo...@gmail.com wrote:
>
> I often wish to perform the action of `subprocess.check_output`, i.e. print
> STDOUT live, and check the return code is 0 on exit. However if there is an
> error, I would like the STDERR to be printed. When looking at log files and
> just seeing the return code is often not very beneficial.
>
> E.g.:
>
> ```py
> subprocess.check_call(['ping', '-c', '1', 'github.com2'])
> ```
>
> Will generate this error:
> ```
> subprocess.CalledProcessError: Command '['ping', '-c', '1', 'github.com2']'
> returned non-zero exit status 2.
> ```
>
> Here we are left wondering why it failed, on real world examples it becomes
> critical to be able to see what the actual error is. So I find I always have
> to wrap such calls in something like this to be able to see STDERR:
>
> ```
> import subprocess
> cmds = ['ping', '-c', '1', 'github.com2']
> result = subprocess.run(cmds, stderr=subprocess.PIPE)
> if result.returncode != 0:
> msg = result.stderr.decode().strip()
> raise subprocess.CalledProcessError(f"CALLED SUBPROCESS ERROR: Command: {'
> '.join(cmds)}\nReturn code {result.returncode}\nSTDERR: {msg}\n")
> ```
>
> With the above one gets to see that STDERR is:
> ```
> ping: github.com2: Temporary failure in name resolution
> ```
I think you are saying you can do what you want with subprocess.run().
What did you need a change to support?
I often wrap code around subprocess.run() to get the exact behaviour that
I need. Seems to work well.
Barry
> _______________________________________________
> Python-ideas mailing list -- python-ideas@python.org
> To unsubscribe send an email to python-ideas-le...@python.org
> https://mail.python.org/mailman3/lists/python-ideas.python.org/
> Message archived at
> https://mail.python.org/archives/list/python-ideas@python.org/message/7PVHSJGKFUIV4ZJFWG7EU3DR6XAGAKQW/
> Code of Conduct: http://python.org/psf/codeofconduct/
>
_______________________________________________
Python-ideas mailing list -- python-ideas@python.org
To unsubscribe send an email to python-ideas-le...@python.org
https://mail.python.org/mailman3/lists/python-ideas.python.org/
Message archived at
https://mail.python.org/archives/list/python-ideas@python.org/message/7F6HKX3FRG6QWEJM57BTCKHKUE2T7BXG/
Code of Conduct: http://python.org/psf/codeofconduct/
