What's a good equivalent to python's subprocess.check
I'd like a good method that matches the interface of subprocess.check_call -- ie, it throws CalledProcessError when it fails, is synchronous, &c -- but instead of returning the return code of the command (if it even does that) returns the program's output, either only stdout, or a tuple of (stdout, stderr).
Does somebody have a method that does this?
Python 2.7+
from subprocess import check_output as qx
Python < 2.7
From subprocess.py:
import subprocess
def check_output(*popenargs, **kwargs):
if 'stdout' in kwargs:
raise ValueError('stdout argument not allowed, it will be overridden.')
process = subprocess.Popen(stdout=subprocess.PIPE, *popenargs, **kwargs)
output, unused_err = process.communicate()
retcode = process.poll()
if retcode:
cmd = kwargs.get("args")
if cmd is None:
cmd = popenargs[0]
raise subprocess.CalledProcessError(retcode, cmd, output=output)
return output
class CalledProcessError(Exception):
def __init__(self, returncode, cmd, output=None):
self.returncode = returncode
self.cmd = cmd
self.output = output
def __str__(self):
return "Command '%s' returned non-zero exit status %d" % (
self.cmd, self.returncode)
# overwrite CalledProcessError due to `output` keyword might be not available
subprocess.CalledProcessError = CalledProcessError
See also Capturing system command output as a string for another example of possible check_output() implementation.
I can not get formatting in a comment, so this is in response to JF Sebastian's answer
I found this very helpful so I figured I would add to this answer. I wanted to be able to work seamlessly in the code without checking the version. This is what I did...
I put the code above into a file called 'subprocess_compat.py'. Then in the code where I use subprocess I did.
import sys
if sys.version_info < (2, 7):
import subprocess_compat
subprocess.check_output = subprocess_compat.check_output
Now anywhere in the code I can just call 'subprocess.check_output' with the params I want and it will work regardless of which version of python I am using.
该函数以字符串列表的形式返回终端输出。
import subprocess,sys
def output(cmd):
cmd_l = cmd.split()
output = subprocess.Popen(cmd_l, stdout=subprocess.PIPE).communicate()[0]
output = output.decode("utf-8")
return (output)
上一篇: 将几个子过程连接在一起