Python实用模块(十一)sh

软硬件环境

• ubuntu 18.04 64bit
• anaconda3 with python 3.7.1
• sh 1.12.14

sh

sh是一个完美替代subprocess的方案，它能帮助你方便的启动其它程序。

安装sh

pip install sh

sh中封装了很多的shell命令，但是官方宣称sh is not a collection of system commands implemented in Python.

In[2]: import sh
In[3]: sh.ifconfig('enp0s25')
Out[3]: 
enp0s25: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.1.182  netmask 255.255.255.0  broadcast 192.168.1.255
        inet6 fe80::9f51:6b1e:2a44:524c  prefixlen 64  scopeid 0x20<link>
        ether 50:7b:9d:d5:13:e6  txqueuelen 1000  (Ethernet)
        RX packets 2107249  bytes 2099954336 (2.0 GB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 1343257  bytes 1630798979 (1.6 GB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
        device interrupt 20  memory 0xe1300000-e1320000  

再看看grep的一个示例，比如我的系统中跑了多个ffmpeg的进程，然后需要找到其中的某一个，获取到进程的pid

xugaoxiang@ubuntu:~$ ps ax | grep ffmpeg
15133 pts/1    S+     1:54 ffmpeg -i rtsp://admin:rm123456@192.168.2.118:554 -c:a copy -c:v copy -y -f flv rtmp://192.168.1.97:2935/live/192.168.2.118:554/index
19252 pts/1    S+     0:00 ffmpeg -i rtsp://admin:rm123456@192.168.2.119:554 -c:a copy -c:v copy -y -f flv rtmp://192.168.1.97:2935/live/192.168.2.119:554/index
19491 pts/6    S+     0:00 grep --color=auto ffmpeg

import sh

def get_pid(expression):
    """

    :param expression: 字符串辨识符，如这里的ip地址 192.168.2.118:554
    :return: 进程的pid
    """

    p = sh.grep(sh.ps("ax"), expression)

    return p.stdout.decode('utf8').lstrip().split(' ')[0]

参考资料

• https://github.com/amoffat/sh
• https://amoffat.github.io/sh/