从 python 运行 linux 命令
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Running a linux command from python
提问by DarylF
I need to run this linux command from python and assign the output to a variable.
我需要从 python 运行这个 linux 命令并将输出分配给一个变量。
ps -ef | grep rtptransmit | grep -v grep
I've tried using pythons commands library to do this.
我试过使用 pythons 命令库来做到这一点。
import commands
a = commands.getoutput('ps -ef | grep rtptransmit | grep -v grep')
But a gets the end of cut off. The output I get is:
但是a得到了切断的结束。我得到的输出是：
'nvr 20714 20711 0 10:39 ? 00:00:00 /opt/americandynamics/venvr/bin/rtptransmit setup_req db=media camera=6 stream=video substream=1 client_a'
but the expected output is:
但预期的输出是：
nvr 20714 20711 0 10:39 ? 00:00:00 /opt/americandynamics/venvr/bin/rtptransmit setup_req db=media camera=6 stream=video substream=1 client_address=192.168.200.179 client_rtp_port=6970 override_lockout=1 clienttype=1
Does anyone know how to stop the output from getting cut off or can anyone suggest another method?
有谁知道如何阻止输出被切断或者有人可以建议另一种方法吗？
采纳答案by lunaryorn
psapparently limits its output to fit into the presumed width of the terminal. You can override this width with the $COLUMNSenvironment variable or with the --columnsoption to ps.
ps显然将其输出限制为适合终端的假定宽度。您可以使用$COLUMNS环境变量或--columns选项覆盖此宽度ps。
The commandsmodule is deprecated. Use subprocessto get the output of ps -efand filter the output in Python. Do not use shell=Trueas suggested by other answers, it is simply superfluous in this case:
该commands模块已弃用。用于在 Python 中subprocess获取输出ps -ef并过滤输出。不要shell=True按照其他答案的建议使用，在这种情况下它只是多余的：
ps = subprocess.Popen(['ps', '-ef', '--columns', '1000'], stdout=subprocess.PIPE)
output = ps.communicate()[0]
for line in output.splitlines():
if 'rtptransmit' in line:
print(line)
You may also want to take a look the pgrepcommand by which you can directly search for specific processes.
您可能还想查看pgrep可以直接搜索特定进程的命令。
回答by fajran
I usually use subprocessfor running an external command. For your case, you can do something like the following
我通常subprocess用于运行外部命令。对于您的情况，您可以执行以下操作
from subprocess import Popen, PIPE
p = Popen('ps -ef | grep rtptransmit | grep -v grep', shell=True,
stdout=PIPE, stderr=PIPE)
out, err = p.communicate()
The output will be in outvariable.
输出将是out可变的。
回答by vartec
commandsis deprecated, you should not use it. Use subprocessinstead
commands已弃用，您不应使用它。使用subprocess替代
import subprocess
a = subprocess.check_output('ps -ef | grep rtptransmit | grep -v grep', shell=True)
回答by sudhams reddy
#!/usr/bin/python
import os
a = os.system("cat /var/log/syslog")
print a
from subprocess import call
b = call("ls -l", shell=True)
print b
import subprocess
cmd = subprocess.check_output('ps -ef | grep kernel', shell=True)
print cmd
Any of the above script will work for you :-)
上述任何脚本都适合您:-)
回答by dru
nano test.py
import os
a = os.system('ps -ef | grep rtptransmit | grep -v grep')
print(a)
python test.py
python3 test.py
Run python file using both python and python3
使用 python 和 python3 运行 python 文件
