python 使用标准库根据进程名获取进程的pid

Posted 2020-10-12

有时候需要获取进程的pid,但又无法使用第三方库的时候.

方法适用linux平台.

方法1

使用subprocess 的check_output函数执行pidof命令

from subprocess import check_output
def get_pid(name):
    return map(int,check_output(["pidof",name]).split())

In [21]: get_pid("chrome")
Out[21]: 
[27698, 27678, 27665, 27649, 27540, 27530,]

　

方法2

使用pgrep命令,pgrep获取的结果与pidof获得的结果稍有不同.pgrep的进程id稍多几个.pgrep命令可以使适用subprocess的check_out函数执行

import subprocess
def get_process_id(name):
    """Return process ids found by (partial) name or regex.

    >>> get_process_id(‘kthreadd‘)
    [2]
    >>> get_process_id(‘watchdog‘)
    [10, 11, 16, 21, 26, 31, 36, 41, 46, 51, 56, 61]  # ymmv
    >>> get_process_id(‘non-existent process‘)
    []
    """
    child = subprocess.Popen([‘pgrep‘, ‘-f‘, name], stdout=subprocess.PIPE, shell=False)
    response = child.communicate()[0]
    return [int(pid) for pid in response.split()]

方法3

直接读取/proc目录下的文件.这个方法不需要启动一个shell,只需要读取/proc目录下的文件即可获取到进程信息.

#!/usr/bin/env python

import os
import sys


for dirname in os.listdir(‘/proc‘):
    if dirname == ‘curproc‘:
        continue

    try:
        with open(‘/proc/{}/cmdline‘.format(dirname), mode=‘rb‘) as fd:
            content = fd.read().decode().split(‘\x00‘)
    except Exception:
        continue

    for i in sys.argv[1:]:
        if i in content[0]:
            print(‘{0:<12} : {1}‘.format(dirname, ‘ ‘.join(content)))

phoemur ~/python $ ./pgrep.py bash
1487         : -bash 
1779         : /bin/bash

　　

4,获取当前脚本的pid进程

import os

os.getpid()