* nice *在subprocess.call函数不起作用

Question

I tried

>>> import subprocess
>>> import os
>>> subprocess.call(["echo","Hello there"], env=os.environ)
Hello there
0
>>> subprocess.call(["nice", "19", "echo","Hello there"], env=os.environ)
nice: 19: No such file or directory
127
>>> subprocess.call(["nice", "19", "echo","Hello there"], env=os.environ, shell=True)
0
0
>>>

I don't understand why subprocess is not recognizing nice there

I have no issues running nice in my shell

$nice -n 19 echo 'hi there'

hi there

Answer 1

Looks like you forgot an argument with "-n" in your subprocess.call call. You probably meant

subprocess.call(["nice", "-n", "19", "echo", "Hello there"], env=os.environ)