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How to Use fcntl for Exclusive File Locking in Python

This code demonstrates how to acquire an exclusive advisory lock on a file using fcntl.flock with a non-blocking flag, simulate work, then release the lock.

fcntl file-locking flock
Python 
import fcntl
import os
import tempfile
import time

def acquire_exclusive_lock(filepath):
    fd = os.open(filepath, os.O_RDWR | os.O_CREAT)
    try:
        fcntl.flock(fd, fcntl.LOCK_EX | fcntl.LOCK_NB)
        print(f"Exclusive lock acquired on {filepath}")
        time.sleep(1)  # Simulate work while holding the l…
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