Create process and pythoncreate process for python System Programming

Create process and pythoncreate process for python System Programming
I. forking process

The process generated by fork has the following features:

• Is a process clone.
• The created process exists independently of the parent process.
• The thread is copied and executed when fork () is called.
  
  • Returns 0 in the Child thread.
  • Returns the pid of the subthread in the parent thread.
  • The PID of the sub-thread is different from that of the parent thread.

Ii. Sample Code

#! /Usr/bin/env pythonimport osdef child_process (): print "I am the child process and my PID is: % d" % OS. getpid () print "teh child is exiting. "def parent_process (): print" I am the parent process whit PID: % d "% OS. getpid () childId = OS. fork () if childId = 0: # child_process () else: # print "inside the parent process" print "my child's pid is: % d "% childId while True: passparent_process ()

After the sub-thread ends, the parent thread is still running and has not been released.

3. New Production threads

• OS .exe c * series Functions
  
  • OS .exe cl
  • OS .exe cle
  • OS .exe cvp
• Child process overwrite parent process
  

It can be found that the created process overwrites the parent process. When the child process ends, the parent process also ends.