#🔒 Checking `subprocess.run` code

16 messages · Page 1 of 1 (latest)

dapper gale
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How does this code look in terms of errors and performance -

  1. Until yesterday, I had no idea what subprocess does. I wrote this code looking at various blogs. Therefore, could someone please have a look and see if I made any glaring error.
  2. Am I missing any convenient feature that experienced programs that add with the run command?
import subprocess
with open("stdout.txt", "w") as stdout, open("stderr.txt", "w") as stderr:
    result = subprocess.run(["bash", "test.sh", "2"], stdout=stdout, stderr=stderr,text=True, check=True)

This is my bash script -

echo "Hello World $1"
printf

printf was added to ensure that an error will be created

Please let me know if you have any questions. Thank you!

vivid lodgeBOT
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@dapper gale

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bright jungle
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You can add capture_output=True, encoding="utf8" if you only have a small amount of output

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text=True does nothing for files passed as stderr/stdout the stderr.fileno()/stdout.fileno() is passed directly to the subprocess to write bytes into

bright jungle
dapper gale
dapper gale
bright jungle
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And it might be clearer to open the files in binary mode

dapper gale
bright jungle
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You'll see that you're still able to view the files

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All text mode does is add a wrapper object that decodes/encodes text to/from bytes

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files can ultimately only contain bytes

dapper gale
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Ah. I see.

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Thank you!

vivid lodgeBOT
#
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