我试图在Python中进行系统调用,并将输出存储为我可以在Python程序中操作的字符串。
#!/usr/bin/python
import subprocess
p2 = subprocess.Popen("ntpq -p")
我尝试了一些事情,包括这里的一些建议:
检索subprocess.call()的输出
但运气不好。
我试图在Python中进行系统调用,并将输出存储为我可以在Python程序中操作的字符串。
#!/usr/bin/python
import subprocess
p2 = subprocess.Popen("ntpq -p")
我尝试了一些事情,包括这里的一些建议:
检索subprocess.call()的输出
但运气不好。
当前回答
在Python 3.7+中,你可以为subprocess.run使用新的capture_output=关键字参数:
import subprocess
p = subprocess.run(["echo", "hello world!"], capture_output=True, text=True)
assert p.stdout == 'hello world!\n'
其他回答
公认的答案仍然很好,只是对更新的功能做了一些评论。从python 3.6开始,你可以直接在check_output中处理编码,参见文档。现在返回一个字符串对象:
import subprocess
out = subprocess.check_output(["ls", "-l"], encoding="utf-8")
在python 3.7中,subprocess.run()中添加了一个参数capture_output,它为我们做了一些Popen/PIPE处理,请参阅python文档:
import subprocess
p2 = subprocess.run(["ls", "-l"], capture_output=True, encoding="utf-8")
p2.stdout
Python 2: http://docs.python.org/2/library/subprocess.html#subprocess.Popen
from subprocess import PIPE, Popen
command = "ntpq -p"
process = Popen(command, stdout=PIPE, stderr=None, shell=True)
output = process.communicate()[0]
print output
在Popen构造函数中,如果shell为True,则应该将命令作为字符串而不是序列传递。否则,只需将命令拆分为一个列表:
command = ["ntpq", "-p"]
process = Popen(command, stdout=PIPE, stderr=None)
如果你还需要读取标准错误到Popen初始化中,你应该将stderr设置为PIPE或STDOUT:
command = "ntpq -p"
process = subprocess.Popen(command, stdout=PIPE, stderr=PIPE, shell=True)
output, error = process.communicate()
注意:从Python 2.7开始,你可以/应该利用subprocess。# subprocess.check_output check_output (https://docs.python.org/2/library/subprocess.html)。
Python 3: https://docs.python.org/3/library/subprocess.html#subprocess.Popen
from subprocess import PIPE, Popen
command = "ntpq -p"
with Popen(command, stdout=PIPE, stderr=None, shell=True) as process:
output = process.communicate()[0].decode("utf-8")
print(output)
注意:如果你的目标只是Python版本高于或等于3.5,那么你可以/应该利用subprocess.run (https://docs.python.org/3/library/subprocess.html#subprocess.run)。
在Python 3.7+中,你可以为subprocess.run使用新的capture_output=关键字参数:
import subprocess
p = subprocess.run(["echo", "hello world!"], capture_output=True, text=True)
assert p.stdout == 'hello world!\n'
我根据其他答案写了一个小函数:
def pexec(*args):
return subprocess.Popen(args, stdout=subprocess.PIPE).communicate()[0].rstrip()
用法:
changeset = pexec('hg','id','--id')
branch = pexec('hg','id','--branch')
revnum = pexec('hg','id','--num')
print('%s : %s (%s)' % (revnum, changeset, branch))
对于python 3.5,我根据前面的回答提出了函数。原木可能被移除,但它很好
import shlex
from subprocess import check_output, CalledProcessError, STDOUT
def cmdline(command):
log("cmdline:{}".format(command))
cmdArr = shlex.split(command)
try:
output = check_output(cmdArr, stderr=STDOUT).decode()
log("Success:{}".format(output))
except (CalledProcessError) as e:
output = e.output.decode()
log("Fail:{}".format(output))
except (Exception) as e:
output = str(e);
log("Fail:{}".format(e))
return str(output)
def log(msg):
msg = str(msg)
d_date = datetime.datetime.now()
now = str(d_date.strftime("%Y-%m-%d %H:%M:%S"))
print(now + " " + msg)
if ("LOG_FILE" in globals()):
with open(LOG_FILE, "a") as myfile:
myfile.write(now + " " + msg + "\n")