process.terminate() method

Method Name:

terminate

Method Signature:

terminate()

Return Value:

NoneType

Parameters:

Not Applicable

Method Overview:

Terminates the process corresponding to the process instance on which it was invoked.
In Unix-like operating systems it uses SIGTERM signal to terminate the process.In Windows it uses TerminateProcess().
It causes the child processes of the terminated process to become orphaned.
After a process is terminated using terminate(), any data passing mechanisms held by the process like Queues, Pipes may become corrupt.
If the process has acquired any synchronization objects this may cause a deadlock to other processes that were waiting on those synchronization objects.

Example:

import multiprocessing as multiproc

import time

# Process function

def pfunc(mq):

for i in range(1,20):

mq.put("Message%d"%i)

time.sleep(1)

print("Child:Populated the Queue with:%d"%i)

if __name__ == "__main__":

# Set the method for process creation

multiproc.set_start_method('fork')

# Create a Queue

mq = multiproc.Queue()

childProc = multiproc.Process(target=pfunc,args=(mq,))

childProc.start()

print("Parent:After child process has started")

time.sleep(2)

# Terminate the child process

childProc.terminate()

print("Parent:After terminate() on the child process")

# Join will return immediately as the process has been terminated already

childProc.join()

print("Parent:Exit code of the child process on terminate():%d"%childProc.exitcode)

if childProc.is_alive() == True:

print(mq.get()) # Queue may be corrupt if process had encountered a terminate() call

Output:

Parent:After child process has started

Child:Populated the Queue with:1

Parent:After terminate() on the child process

Parent:Exit code of the child process on terminate():-1

Process.terminate() method