app/django/utils/daemonize.py
author Madhusudan C.S. <madhusudancs@gmail.com>
Fri, 05 Jun 2009 21:27:03 +0200
changeset 2397 d943fa182fae
parent 323 ff1a9aa48cfd
permissions -rw-r--r--
Moved the GHOP module into the modules package. This also includes moving the templates and content into their respective place inside the Soc folder. This is to avoid adding every folder to the app.yaml file. Patch by: Madhusudan C.S. and Lennard de Rijk Reviewed by: Lennard de Rijk

import os
import sys

if os.name == 'posix':
    def become_daemon(our_home_dir='.', out_log='/dev/null',
                      err_log='/dev/null', umask=022):
        "Robustly turn into a UNIX daemon, running in our_home_dir."
        # First fork
        try:
            if os.fork() > 0:
                sys.exit(0)     # kill off parent
        except OSError, e:
            sys.stderr.write("fork #1 failed: (%d) %s\n" % (e.errno, e.strerror))
            sys.exit(1)
        os.setsid()
        os.chdir(our_home_dir)
        os.umask(umask)

        # Second fork
        try:
            if os.fork() > 0:
                os._exit(0)
        except OSError, e:
            sys.stderr.write("fork #2 failed: (%d) %s\n" % (e.errno, e.strerror))
            os._exit(1)

        si = open('/dev/null', 'r')
        so = open(out_log, 'a+', 0)
        se = open(err_log, 'a+', 0)
        os.dup2(si.fileno(), sys.stdin.fileno())
        os.dup2(so.fileno(), sys.stdout.fileno())
        os.dup2(se.fileno(), sys.stderr.fileno())
        # Set custom file descriptors so that they get proper buffering.
        sys.stdout, sys.stderr = so, se
else:
    def become_daemon(our_home_dir='.', out_log=None, err_log=None, umask=022):
        """
        If we're not running under a POSIX system, just simulate the daemon
        mode by doing redirections and directory changing.
        """
        os.chdir(our_home_dir)
        os.umask(umask)
        sys.stdin.close()
        sys.stdout.close()
        sys.stderr.close()
        if err_log:
            sys.stderr = open(err_log, 'a', 0)
        else:
            sys.stderr = NullDevice()
        if out_log:
            sys.stdout = open(out_log, 'a', 0)
        else:
            sys.stdout = NullDevice()

    class NullDevice:
        "A writeable object that writes to nowhere -- like /dev/null."
        def write(self, s):
            pass