Source code for daemonize

"""Module to daemonize the current process on Unix."""
# (C) Pywikibot team, 2007-2022
# Distributed under the terms of the MIT license.
from __future__ import annotations

import os
import stat
import sys
from pathlib import Path

is_daemon = False

[docs] def daemonize(close_fd: bool = True, chdir: bool = True, redirect_std: str | None = None) -> None: """Daemonize the current process. Only works on POSIX compatible operating systems. The process will fork to the background and return control to terminal. :param close_fd: Close the standard streams and replace them by /dev/null :param chdir: Change the current working directory to / :param redirect_std: Filename to redirect stdout and stdin to """ # Fork away if not os.fork(): # Become session leader os.setsid() # Fork again to prevent the process from acquiring a # controlling terminal pid = os.fork() if not pid: global is_daemon is_daemon = True if close_fd: os.close(0) os.close(1) os.close(2)'/dev/null', os.O_RDWR) if redirect_std: # R/W mode without execute flags mode = (stat.S_IRUSR | stat.S_IWUSR | stat.S_IRGRP | stat.S_IWGRP | stat.S_IROTH | stat.S_IWOTH), os.O_WRONLY | os.O_APPEND | os.O_CREAT, mode) else: os.dup2(0, 1) os.dup2(1, 2) if chdir: os.chdir('/') return # Write out the pid path = Path(Path(sys.argv[0]).name).with_suffix('.pid') path.write_text(str(pid), encoding='uft-8') # Exit to return control to the terminal # os._exit to prevent the cleanup to run os._exit(os.EX_OK)