def main():
print('Process (%s) start...' % os.getpid())
# Only works on Unix/Linux/Mac:
pid = os.fork()
if pid == 0:
print('I am child process (%s) and my parent is %s.' % (os.getpid(), os.getppid()))
else:
print('I (%s) just created a child process (%s).' % (os.getpid(), pid))
print('Parent process %s.' % os.getpid())
p = Process(target=run_proc, args=('test',))
print('Child process will start.')
p.start()
p.join()
print('Child process end.')
print '================================'
print('Parent process %s.' % os.getpid())
p = Pool(4)
for i in range(5):
p.apply_async(long_time_task, args=(i,))
print('Waiting for all subprocesses done...')
p.close()
p.join()
print('All subprocesses done.')
print('$ nslookup www.python.org')
r = subprocess.call(['nslookup', 'www.python.org'])
print('Exit code:', r)
print('$ nslookup')
p = subprocess.Popen(['nslookup'], stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
output, err = p.communicate(b'set q=mx\npython.org\nexit\n')
print(output.decode('utf-8'))
print('Exit code:', p.returncode)
if __name__=='__main__':
print('Parent process %s.' % os.getpid())
p = Pool(4)
for i in range(5):
p.apply_async(long_time_task, args=(i,))
print('Waiting for all subprocesses done...')
p.close()
p.join()
print('All subprocesses done.')
"""对Pool对象调用join()方法会等待所有子进程执行完毕，调用join()之前必须先调用close()，调用close()之后就不能继续添加新的Process了。
请注意输出的结果，task 0，1，2，3是立刻执行的，而task 4要等待前面某个task完成后才执行，这是因为Pool的默认大小在我的电脑上是4，因此，最多同时执行4个进程。这是Pool有意设计的限制，并不是操作系统的限制。如果改成：
p = Pool(5)
就可以同时跑5个进程。
由于Pool的默认大小是CPU的核数，如果你不幸拥有8核CPU，你要提交至少9个子进程才能看到上面的等待效果。"""
#子进程
"""很多时候，子进程并不是自身，而是一个外部进程。我们创建了子进程后，还需要控制子进程的输入和输出。
subprocess模块可以让我们启动一个子进程,然后控制其输入和输出
下面的例子演示了如何在Python代码中运行命令nslookup www.python.org，这和命令行直接运行的效果是一样的："""
import subprocess
print('$ nslookup www.python.org')
r = subprocess.call(['nslookup','www.python.org'])
print('Exit code:',r)
"""如果子进程还需要输入，则可以通过communicate()方法输入："""
import subprocess
print('$ nslookup')
p = subprocess.Popen(['nslookup'], stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
output, err = p.communicate(b'set q=mx\npython.org\nexit\n')
print(output.decode('utf-8'))
print('Exit code:', p.returncode)
������#服务器: UnKnown
Address: 192.168.43.1
����#名称: dualstack.python.map.fastly.net
Addresses: 2a04:4e42:11::223
151.101.228.223
Aliases: www.python.org
Exit code: 0
# 如果子进程还需要输入，则可以通过communicate()方法输入：
import subprocess
print('$ nslookup')
p = subprocess.Popen(['nslookup'], stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
output, err = p.communicate(b'set q=mx\npython.org\nexit\n')
print(output.decode('utf-8'))
print('Exit code:', p.returncode)
# 上面的代码相当于在命令行执行命令nslookup，然后手动输入：
set q=mx
python.org
exit
# 运行结果
$ nslookup
Server: 192.168.19.4
Address: 192.168.19.4#53
Non-authoritative answer:
python.org mail exchanger = 50 mail.python.org.
concat_files_4 = "cat window_*_montage_4.txt > " + name[-1] + "_4.txt" concat_files_5 = "cat window_*_montage_5.txt > " + name[-1] + "_5.txt" concat_files_6 = "cat window_*_montage_6.txt > " + name[-1] + "_6.txt" concat_files_7 = "cat window_*_montage_7.txt > " + name[-1] + "_7.txt" concat_files_8 = "cat window_*_montage_8.txt > " + name[-1] + "_8.txt" concat_files_9 = "cat window_*_montage_9.txt > " + name[-1] + "_9.txt" concat_files_10 = "cat window_*_montage_10.txt > " + name[-1] + "_10.txt" concat_files_11 = "cat window_*_montage_11.txt > " + name[-1] + "_11.txt" concat_files_seiz = "cat window_*_seizure_results.txt > " + name[-1] + "_seiz.txt" d = "/home/pi/algorithm/UI/data" p1 = Popen(["ls", "-tr"], cwd=d,stdout=PIPE) p2 = Popen(concat_files_0 ,shell=True, cwd = d, stdin=p1.stdout,stdout=PIPE) p2.communicate()[0] p2 = Popen(concat_files_1 ,shell=True, cwd = d, stdin=p1.stdout,stdout=PIPE) p2.communicate()[0] p2 = Popen(concat_files_2 ,shell=True, cwd = d, stdin=p1.stdout,stdout=PIPE) p2.communicate()[0] p2 = Popen(concat_files_3 ,shell=True, cwd = d, stdin=p1.stdout,stdout=PIPE) p2.communicate()[0] p2 = Popen(concat_files_4 ,shell=True, cwd = d, stdin=p1.stdout,stdout=PIPE) p2.communicate()[0] p2 = Popen(concat_files_5 ,shell=True, cwd = d, stdin=p1.stdout,stdout=PIPE) p2.communicate()[0]
print('fork: \nProcess (%s) start...' % os.getpid())
pid = os.fork() # fork 轻松创建子进程
if pid == 0: # 子进程返回 0, 父进程返回子进程的 id, getppid() 得到父进程 pid
print('I am child process (%s) and my parent is (%s).' % (os.getpid(), os.getppid()))
exit(0) # 子进程执行打这里就退出, 不执行后面的
else: print('I (%s) just created a child process (%s).' % (os.getpid(), pid))
##################################################################
## multiprocessing Process
from multiprocessing import Process # fork 无法在 Windows 上运行, Process 可以跨平台
def run_proc(name): print('Run child process %s (%s)...' % (name, os.getpid())) # 子进程要执行的代码
print('\nProcess: \nParent process (%s).' % os.getpid())
p = Process(target=run_proc, args=('test',)) # 参数在 args 中传
p.start() # start() 方法启动, 这样创建进程比 fork() 还要简单
p.join() # join() 方法可以等待子进程结束后再继续往下运行, 通常用于进程间的同步
##################################################################
## subprocess
import subprocess # 启动一个子进程, 然后控制其输入和输出
print('\nsubprocess 没有控制输入输出: \n$ nslookup www.python.org') # 不用控制的
r = subprocess.call(['nslookup', 'www.python.org']); print('Exit code:', r)
print('\nsubprocess 控制输入输出: $ nslookup')
p = subprocess.Popen(['nslookup'], stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
output, err = p.communicate(b'set q=mx\npython.org\nexit\n') # 相当于下面三条命令: set q=mx; python.org; exit
print(output.decode('utf-8'))
print('Exit code:', p.returncode)
p = subprocess.Popen(['nslookup'], stdin=sys.stdin, stdout=sys.stdout, stderr=sys.stderr)
p.wait() # 加上这句话才能在终端等待输入...
p.kill()
print(p.returncode) # 手动结束的话不会执行到这里, 执行到 kill() 后就会报错 KeyboardInterrupt
class SensorHubManager(object):
def __init__(self, path):
self.path = path
self._changed_files = []
self._deleted_files = []
self._running_scripts = []
self._lpath = None
self._running = True
self._mt = None
self._threads = {}
def start_service(self, scripts_to_run):
self._running_scripts = scripts_to_run
for s in self._running_scripts:
self._threads[s] = run_script(os.path.join(self.path, s))
self._mt = Process(target=self.monitor_thread)
self._mt.start()
def stop_service(self):
self._running = False
time.sleep(1) # wait some time in case it can stop
self._mt.terminate()
o, e = self._mt.communicate()
print 'Terminate main thread: out=%s, err=%s' % (o, e)
for t in self._threads:
self._threads[t].kill()
o, e = self._threads[t].communicate()
print 'Terminate %s: out=%s, err=%s' % (t, o, e)
print 'All threads are killed'
time.sleep(1)
def monitor_thread(self):
print 'Starting monitor thread'
while self._running:
print 'checking workspace...'
self.running_scripts_check()
self.sync_with_server()
self.check_running_files()
self.action_required()
time.sleep(CHECKING_SECONDS)
print 'Monitor thread is terminated'
def running_scripts_check(self):
dead_threads = []
for t in self._threads:
if not is_running(self._threads[t]):
dead_threads.append(t)
for t in dead_threads:
del self._threads[t]
self._threads[t] = run_script(os.path.join(self.path, t))
if dead_threads:
print 'Start dead threads: %s' % dead_threads
def sync_with_server(self):
t = time.localtime()
self._lpath = 'tempdir-%04d%02d%02d%02d%02d%02d' % (
t.tm_year, t.tm_mon, t.tm_mday, t.tm_hour, t.tm_min, t.tm_sec)
if os.path.exists(self._lpath):
os.system('rm -rf %s' % self._lpath)
os.system('git clone -q %s %s' % (REPO, self._lpath))
def check_running_files(self):
print 'running scripts: %s' % self._running_scripts
self._changed_files = []
self._deleted_files = []
if not os.path.exists(self.path):
os.system('cp -r %s %s' % (self._lpath, self.path))
self._changed_files.extend(valid_files(self.path))
print 'create new workspace at %s' % self.path
return
for f in valid_files(self._lpath):
srcf = os.path.join(self._lpath, f)
dstf = os.path.join(self.path, f)
if not os.path.exists(dstf) or not file_identical(srcf, dstf):
os.system("cp %s %s" %
(os.path.join(self._lpath, f), self.path))
self._changed_files.append(f)
dst_files = valid_files(self.path)
src_files = valid_files(self._lpath)
if len(dst_files) > len(src_files):
for f in dst_files:
if not f in src_files:
os.system('rm -rf %s' % os.path.join(self.path, f))
self._deleted_files.append(f)
if self._changed_files:
print 'changed files: %s' % self._changed_files
if self._deleted_files:
print 'deleted files: %s' % self._deleted_files
def action_required(self):
for f in self._running_scripts:
if f in self._changed_files + self._deleted_files:
if f in self._threads and is_running(self._threads[f]):
self._threads[f].kill()
print 'script %s is killed' % f
del self._threads[f]
if f in self._changed_files:
self._threads[f] = run_script(os.path.join(self.path, f))
print 'script %s is started' % f
os.system('rm -rf %s' % self._lpath)
# 需要注意，由于我们创建Pool对象的时候传入参数4，所以在task 4的时候需要等待0 1 2 3中有一个完成，才会执行，不是操作系统的限制。
# 由于Pool默认大小是CPU的核数，所以
## 子进程： 很多时候子进程并不是自身，而是一个外部的进程，创建子进程后还需要控制器输入和输出。
import subprocess
print('nslookup www.python.org')
r = subprocess.call(['nslookup','www.python.org']) # 创建子进程，并执行一个命令
print('Exit code:',r)
## 如果子进程需要输入内容，使用communicate()输入
import subprocess
print("$ nslookup")
p = subprocess.Popen(['nslookup'],stdin=subprocess.PIPE,stdout=subprocess.PIPE,stderr=subprocess.PIPE)
output,err = p.communicate(b'set q=mx\npython.org\nexit\n')# 相当于在命令行执行 nslookup，再手动输入参数
print(output.decode('utf-8'))
print('Exit code:',p.returncode)
## 进程间通信
from multiprocessing import Process,Queue
import os,time,random
def write(q):
print('Process to write:%s'%os.getpid())
for v in ['A','B','C','D']:
print('Put %s to queue...'%v)
q.put(v)
time.sleep(random.random())
print('\nProcess: \nParent process (%s).' % os.getpid())
p = Process(target=run_proc, args=('test',)) # 参数在 args 中传
p.start() # start() 方法启动, 这样创建进程比 fork() 还要简单
p.join() # join() 方法可以等待子进程结束后再继续往下运行, 通常用于进程间的同步
##################################################################
# Pool time
from multiprocessing import Pool # 在 Process 基础上启动大量子进程
# def long_time_task(name):
# print('Run task %s (%s)...' % (name, os.getpid()))
# start = time.time(); time.sleep(random.random() * 3)
# end = time.time(); print('Task %s runs %0.2f seconds.' % (name, (end - start)))
# print('\nPool: \nParent process %s.' % os.getpid())
# p = Pool(4) # 大小为 4 的线程池, 所以下面 前4个 进程特别快就生成了, 第5个 需要等其中一个运行完
# for i in range(5): p.apply_async(long_time_task, args=(i,))
# p.close() # 调用 close() 之后就不能继续添加新的 Process 了
# p.join() # Pool 对象调用 join() 方法会等待所有子进程执行完毕, 调用 join() 之前必须先调用 close()
##################################################################
# subprocess
import subprocess # 启动一个子进程, 然后控制其输入和输出
print('\nsubprocess 没有控制输入输出: \n$ nslookup www.python.org') # 不用控制的
r = subprocess.call(['nslookup', 'www.python.org']); print('Exit code:', r)
print('\nsubprocess 控制输入输出: $ nslookup')
p = subprocess.Popen(['nslookup'], stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
output, err = p.communicate(b'set q=mx\npython.org\nexit\n') # 相当于下面三条命令: set q=mx; python.org; exit
print(output.decode('utf-8'))
print('Exit code:', p.returncode)
p = subprocess.Popen(['nslookup'], stdin=sys.stdin, stdout=sys.stdout, stderr=sys.stderr)
p.wait() # 加上这句话才能在终端等待输入...
p.kill()
print(p.returncode) # 手动结束的话不会执行到这里, 执行到 kill() 后就会报错 KeyboardInterrupt
# Address: 222.222.222.222
#
# ����: python.map.fastly.net
# Addresses: 2a04:4e42:36::223
# 151.101.228.223
# Aliases: www.python.org
#
# Exit code: 0
# 如果子进程还需要输入，则可以通过communicate()方法输入：
import subprocess
print('$ nslookup')
p=subprocess.Popen(['nslookup'],stdin=subprocess.PIPE,stderr=subprocess.PIPE)
# output,err=p.communicate(b'set q=mx\nbaidu.com\nexit\n')
p.communicate(b'set q=mx\npython.org\nexit\n')# 此方法没有返回数 ， 所以要输出上面的output err 都是NoneType
# 上面的代码相当于在命令行执行命令nslookup，然后手动输入：
# set q=mx
# python.org
# exit
print('Exit code：',p.returncode);
# $ nslookup
# Ĭ�Ϸ�����: SJZ-CA6-ZONE2
# Address: 222.222.222.222
#
# > > ������: SJZ-CA6-ZONE2
# Address: 222.222.222.222
#
# python.org MX preference = 50, mail exchanger = mail.python.org
# > Exit code： 0
while True:
print('Run child process %s (%s)...' % name,(os.getpid()))
print('读取数据....')
value = q.get(True)
print('Get %s from queue.' % value)
'''
if __name__ == '__main__':
print('Parent process %s.' % os.getpid())
q = Queue()
p = Process(target=run_proc, args=(
"haha",
q,
))
#pr = Process(target=read, args=(q,))
p = Process(target=run_proc, args=(
'名字',
q,
))
print('Child process will start.')
p.start()
p.join()
print('Child process end.')
print("$ nslookup")
p = subprocess.Popen(['nslookup'],
stdin=subprocess.PIPE,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
output, err = p.communicate(b'set q=mx\n10.123.65.56\nexit\n')
print(output.decode('gbk'))
print('Exit code:', p.returncode)
# 退出子线程！ 0
"""
如果需要输入！
"""
print("准备启动一个子线程 ====== 2")
p = subprocess.Popen(['nslookup'],
stdin=subprocess.PIPE,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
out ,err = p.communicate(b"set q=mx\npython.org\nexit\n")
# 上面的代码相当于在命令行执行命令nslookup，然后手动输入：
# set q=mx
# python.org
# exit
print(out.decode('utf-8'))
print("Exit code:", p.returncode)
# 准备启动一个子线程 ====== 2
# Server: 192.168.1.1
# Address: 192.168.1.1#53
# Non-authoritative answer:
# python.org mail exchanger = 50 mail.python.org.
#############################
import subprocess
print('====== subprocess ======')
# 查询 baidu ip
print('$ nslookup www.baidu.com')
r = subprocess.call(['nslookup', 'www.baidu.com'])
print('Exit code:', r)
# 如果子进程需要输入
print('$ nslookup')
p = subprocess.Popen(['nslookup'],
stdin=subprocess.PIPE,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
output, err = p.communicate(b'set q=mx\nwww.baidu.com\nexit\n')
print(output.decode('utf-8'))
print('Exit code:', p.returncode)
#############################
# 进程间通信: Queue 消息队列
#############################
from multiprocessing import Process, Queue
print('====== multiprocessing.Queue ======')
def producer(q):
for fruit in ['apple', 'tangerine', 'orange', 'banana']:
print(' > produce "%s"' % fruit)
q.put(fruit)
