Other methods are two ways to concurrent multi-threaded programming ~ ~ ~ ~ ~ ~ open thread, the thread

What is a thread

A thread is the smallest unit of program execution, the process is like an assembly line work.

Open a process: a process of open space in memory, then all the resources of a copy of the data in the primary process, then the calling thread to execute code

Process is resource unit, thread is a unit of execution

VS process two threads

1. Open process overhead is very large, much larger than the cost of open thread
2. Open thread speed is very fast, faster several times to hundreds of times
3. The same process can be shared between threads and thread data, we need the help of the queue and other methods to communicate between processes and processes.
4. The main thread and the child thread no separate status of (no primary or secondary), after the end of a main thread to wait for the end of the other sub-thread to the end of the process.

Two ways to open three threads

from threading import Thread
import time
def task(name):
    print(f'{name}is running')
    time.sleep(1)
    print(f'{name}is gone')

if __name__ == '__main__':
    t1 = Thread(target=task,args=('大黑',))
    t1.start()
    print('主线程')

from threading import Thread
import time
class MyThread(Thread):
    def __init__(self,name):
        super().__init__()
        self.name = name

    def run(self):
        print(f'{self.name}is running')
        time.sleep(1)
        print(f'{self.name}is gone')

if __name__ == '__main__':
    t1 = MyThread('大黑')
    t1.start()
    print('主进程')

Other methods of four threads

from threading import Thread,currentThread,enumerate,activeCount
import os,time
def task():
    print(currentThread())
    time.sleep(1)
    print('666')

if __name__ == '__main__':
    t1 = Thread(target=task,name='线程1')
    t2 = Thread(target=task,name='线程2')
    t1.start()
    t2.start()
    time.sleep(2)
    print(t1.isAlive()) # 判断线程是否活着
    print(t1.getName()) # 获取线程名
    t1.setName('子进程1') # 设置线程名
    print(t1.getName())
    print(currentThread()) # 获取当前线程的对象
    print(enumerate()) # 返回一个列表,包含所有的线程对象
    print(activeCount()) # 返回正在运行的线程数量
    print(f'主线程{os.getpid()}')