How to use a process in a subclass

To implement a custom subclass and process, we must:

• Define a new subclass of the Process class

• Override the _init__(self [,args]) method to add additional arguments

• Override the run(self [,args]) method to implement what Process should when it is started

Once you have created the new Process subclass, you can create an instance of it and then start by invoking the start() method, which will in turn call the run() method.

How to do it...

We will rewrite the first example in this manner:

#Using a process in a subclass Chapter 3: Process Based #Parallelism

import multiprocessing

class MyProcess(multiprocessing.Process):
    def run(self):
        print ('called run method in process: %s' %self.name)
        return

if __name__ == '__main__':
    jobs = []
    for i in range(5):
        p = MyProcess ()
        jobs.append(p)
        p.start()
        p.join()

To run the script from the Command Prompt, type the following command:

python subclass_process.py

The result...