How to check screen is running?

问题

How to check in Python whether the screen with the given name. For example, check if server1 is running?

Thanks : )

回答1:

The built in command for finding current screen sessions is screen -ls

To get the same functionality in python:

from subprocess import check_output

def screen_present(name):
        var = check_output(["screen -ls; true"],shell=True)
        if "."+name+"\t(" in var:
                print name+" is running"
        else:
                print name+" is not running"

screen_present("server1")

A couple of comments on the code:

I had to use ; true and shell=True because screen returns a exit code of 1, which doesn't play well with the check_output function.
Also, I added the "."+ and +\t( to make sure that we were matching the screen name and not another part of the printout.

回答2:

you could use subprocess and pgrep:

import subprocess

p = subprocess.check_output(['pgrep', '-f', 'screen'])
print p

回答3:

First off, what are you trying to achieve? You know that you can simply reattach a running screen session, do you?

screen -DRS admin # creates a new session if it isn't running

Likewise use screen -x -S admin to share the admin session without force-detaching the connected user(s).

Direct answer:

You can simply use the output of

screen -ls

which lists all running sessions, showing whether they are attached as well:

There are screens on:
        6675.third      (11/04/2011 09:25:49 PM)        (Attached)
        6668.pts-2.koolu        (11/04/2011 09:25:38 PM)        (Attached)
        6644.admin      (11/04/2011 09:25:21 PM)        (Detached)
3 Sockets in /var/run/screen/S-sehe.

来源：https://stackoverflow.com/questions/8015163/how-to-check-screen-is-running

标签

python

gnu-screen