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]
