From 3129de1e037dbce80813ec7b29e21598ad09f738 Mon Sep 17 00:00:00 2001 From: Benjamin Peterson Date: Wed, 11 Jun 2008 02:40:25 +0000 Subject: add the multiprocessing package to fulfill PEP 371 --- Lib/multiprocessing/__init__.py | 269 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 269 insertions(+) create mode 100644 Lib/multiprocessing/__init__.py (limited to 'Lib/multiprocessing/__init__.py') diff --git a/Lib/multiprocessing/__init__.py b/Lib/multiprocessing/__init__.py new file mode 100644 index 0000000000..5352be041a --- /dev/null +++ b/Lib/multiprocessing/__init__.py @@ -0,0 +1,269 @@ +# +# Package analogous to 'threading.py' but using processes +# +# multiprocessing/__init__.py +# +# This package is intended to duplicate the functionality (and much of +# the API) of threading.py but uses processes instead of threads. A +# subpackage 'multiprocessing.dummy' has the same API but is a simple +# wrapper for 'threading'. +# +# Try calling `multiprocessing.doc.main()` to read the html +# documentation in in a webbrowser. +# +# +# Copyright (c) 2006-2008, R Oudkerk +# All rights reserved. +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions +# are met: +# +# 1. Redistributions of source code must retain the above copyright +# notice, this list of conditions and the following disclaimer. +# 2. Redistributions in binary form must reproduce the above copyright +# notice, this list of conditions and the following disclaimer in the +# documentation and/or other materials provided with the distribution. +# 3. Neither the name of author nor the names of any contributors may be +# used to endorse or promote products derived from this software +# without specific prior written permission. +# +# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" AND +# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE +# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +# + +__version__ = '0.70a1' + +__all__ = [ + 'Process', 'current_process', 'active_children', 'freeze_support', + 'Manager', 'Pipe', 'cpu_count', 'log_to_stderr', 'get_logger', + 'allow_connection_pickling', 'BufferTooShort', 'TimeoutError', + 'Lock', 'RLock', 'Semaphore', 'BoundedSemaphore', 'Condition', + 'Event', 'Queue', 'JoinableQueue', 'Pool', 'Value', 'Array', + 'RawValue', 'RawArray' + ] + +__author__ = 'R. Oudkerk (r.m.oudkerk@gmail.com)' + +# +# Imports +# + +import os +import sys + +import _multiprocessing +from multiprocessing.process import Process, current_process, active_children + +# +# Exceptions +# + +class ProcessError(Exception): + pass + +class BufferTooShort(ProcessError): + pass + +class TimeoutError(ProcessError): + pass + +class AuthenticationError(ProcessError): + pass + +# +# Definitions not depending on native semaphores +# + +def Manager(): + ''' + Returns a manager associated with a running server process + + The managers methods such as `Lock()`, `Condition()` and `Queue()` + can be used to create shared objects. + ''' + from multiprocessing.managers import SyncManager + m = SyncManager() + m.start() + return m + +def Pipe(duplex=True): + ''' + Returns two connection object connected by a pipe + ''' + from multiprocessing.connection import Pipe + return Pipe(duplex) + +def cpu_count(): + ''' + Returns the number of CPUs in the system + ''' + if sys.platform == 'win32': + try: + num = int(os.environ['NUMBER_OF_PROCESSORS']) + except (ValueError, KeyError): + num = 0 + elif sys.platform == 'darwin': + try: + num = int(os.popen('sysctl -n hw.ncpu').read()) + except ValueError: + num = 0 + else: + try: + num = os.sysconf('SC_NPROCESSORS_ONLN') + except (ValueError, OSError, AttributeError): + num = 0 + + if num >= 1: + return num + else: + raise NotImplementedError('cannot determine number of cpus') + +def freeze_support(): + ''' + Check whether this is a fake forked process in a frozen executable. + If so then run code specified by commandline and exit. + ''' + if sys.platform == 'win32' and getattr(sys, 'frozen', False): + from multiprocessing.forking import freeze_support + freeze_support() + +def get_logger(): + ''' + Return package logger -- if it does not already exist then it is created + ''' + from multiprocessing.util import get_logger + return get_logger() + +def log_to_stderr(level=None): + ''' + Turn on logging and add a handler which prints to stderr + ''' + from multiprocessing.util import log_to_stderr + return log_to_stderr(level) + +def allow_connection_pickling(): + ''' + Install support for sending connections and sockets between processes + ''' + from multiprocessing import reduction + +# +# Definitions depending on native semaphores +# + +def Lock(): + ''' + Returns a non-recursive lock object + ''' + from multiprocessing.synchronize import Lock + return Lock() + +def RLock(): + ''' + Returns a recursive lock object + ''' + from multiprocessing.synchronize import RLock + return RLock() + +def Condition(lock=None): + ''' + Returns a condition object + ''' + from multiprocessing.synchronize import Condition + return Condition(lock) + +def Semaphore(value=1): + ''' + Returns a semaphore object + ''' + from multiprocessing.synchronize import Semaphore + return Semaphore(value) + +def BoundedSemaphore(value=1): + ''' + Returns a bounded semaphore object + ''' + from multiprocessing.synchronize import BoundedSemaphore + return BoundedSemaphore(value) + +def Event(): + ''' + Returns an event object + ''' + from multiprocessing.synchronize import Event + return Event() + +def Queue(maxsize=0): + ''' + Returns a queue object + ''' + from multiprocessing.queues import Queue + return Queue(maxsize) + +def JoinableQueue(maxsize=0): + ''' + Returns a queue object + ''' + from multiprocessing.queues import JoinableQueue + return JoinableQueue(maxsize) + +def Pool(processes=None, initializer=None, initargs=()): + ''' + Returns a process pool object + ''' + from multiprocessing.pool import Pool + return Pool(processes, initializer, initargs) + +def RawValue(typecode_or_type, *args): + ''' + Returns a shared object + ''' + from multiprocessing.sharedctypes import RawValue + return RawValue(typecode_or_type, *args) + +def RawArray(typecode_or_type, size_or_initializer): + ''' + Returns a shared array + ''' + from multiprocessing.sharedctypes import RawArray + return RawArray(typecode_or_type, size_or_initializer) + +def Value(typecode_or_type, *args, **kwds): + ''' + Returns a synchronized shared object + ''' + from multiprocessing.sharedctypes import Value + return Value(typecode_or_type, *args, **kwds) + +def Array(typecode_or_type, size_or_initializer, **kwds): + ''' + Returns a synchronized shared array + ''' + from multiprocessing.sharedctypes import Array + return Array(typecode_or_type, size_or_initializer, **kwds) + +# +# +# + +if sys.platform == 'win32': + + def set_executable(executable): + ''' + Sets the path to a python.exe or pythonw.exe binary used to run + child processes on Windows instead of sys.executable. + Useful for people embedding Python. + ''' + from multiprocessing.forking import set_executable + set_executable(executable) + + __all__ += ['set_executable'] -- cgit v1.2.1