Is python's print synchronized?

Question

Is python\'s print synchronized? :)

Between Threads.

Answer 1

Kind of workaround... It does not print synchronized, but it is monolithic and thus the threads will not write on top of each other.

Pros: Does not require locking and thus is faster.

Cons:

• It is not synchronized and there is no guarantee the events will be printed in the order happened. As a side effect, if an exception appears, the text of the exception might start before the last few prints are out. They might show up after the exception text or somewhere in the middle of the stack trace.
• Takes a bit more time and memory to run the loop.

import threading, time


class SomeThread(threading.Thread):
    def __init__(self, name):
        super().__init__()
        self.name = name
        ...

    def mono_print(self, *v):
        p = time.strftime("%Y-%m-%d %H:%M:%S") + ' ' + self.name
        for s in v:
            p += ' ' + str(s)
        print(p + '\n', end='', flush=True)

    def run(self):
        self.mono_print('thread is running.')

        ...

        self.mono_print('something', 'them something else')

        ...

        self.mono_print('processed')