python subprocess模块 监控子进程的2种方式 忙等待和立即返回同时设置子进程超时时间 转

http://guozhiwei.iteye.com/blog/973793

一:循环 忙等 子进程结束

import subprocess  
import os  
import time  
tt = '555'  
cmd = "python /home/100003/python/mypython/sub2.py "+" 333"+" 444 "+tt  
print time.time()  
sub2 = subprocess.Popen(cmd, shell=True)  
while 1:  
    ret1 = subprocess.Popen.poll(sub2)  
    if ret1 == 0:  
        print sub2.pid,'end'  
        break  
    elif ret1 is None:  
        print  'running'  
        time.sleep(1)  
    else:  
        print sub2.pid,'term'  
        break  
print time.time()  

二:子进程结束 立即返回 使用select模块 同时可设置子进程的超时时间

import subprocess  
import select  
import time  
import signal  
import os  
  
tt = '555'  
cmd = "python /home/100003/python/mypython/sub2.py "+" 333"+" 444 "+tt  
timeout = 3  
pro = subprocess.Popen(cmd, stdout=subprocess.PIPE,shell = True)  
print time.time()  
while 1:  
    while_begin = time.time()  
    print 'timeout',timeout  
    fs = select.select([pro.stdout], [], [], timeout)  
    if pro.stdout in fs[0]:  
        tmp = pro.stdout.read()  
        print 'read', tmp  
        if not tmp:  
            print 'end'  
            print time.time()  
            break  
    else:  
        print 'outoftime'  
        print os.kill(pro.pid, signal.SIGKILL),  
        break  
    timeout = timeout - (time.time() - while_begin)