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Direktori : /lib64/python2.7/site-packages/zmq/utils/ |
Current File : //lib64/python2.7/site-packages/zmq/utils/win32.pyo |
� +�{Wc @ s� d Z d d l Z d e f d � � YZ e j d k r� d d l m Z m Z d d l m Z m Z e j d � Z e e e � Z e j Z e e f e _ e e _ d e f d � � YZ n d e f d � � YZ d S( s Win32 compatibility utilities.i����Nt _allow_interruptc B s5 e Z d Z d d � Z d � Z d � Z d � Z RS( sD Utility for fixing CTRL-C events on Windows. On Windows, the Python interpreter intercepts CTRL-C events in order to translate them into ``KeyboardInterrupt`` exceptions. It (presumably) does this by setting a flag in its "console control handler" and checking it later at a convenient location in the interpreter. However, when the Python interpreter is blocked waiting for the ZMQ poll operation to complete, it must wait for ZMQ's ``select()`` operation to complete before translating the CTRL-C event into the ``KeyboardInterrupt`` exception. The only way to fix this seems to be to add our own "console control handler" and perform some application-defined operation that will unblock the ZMQ polling operation in order to force ZMQ to pass control back to the Python interpreter. This context manager performs all that Windows-y stuff, providing you with a hook that is called when a CTRL-C event is intercepted. This hook allows you to unblock your ZMQ poll operation immediately, which will then result in the expected ``KeyboardInterrupt`` exception. Without this context manager, your ZMQ-based application will not respond normally to CTRL-C events on Windows. If a CTRL-C event occurs while blocked on ZMQ socket polling, the translation to a ``KeyboardInterrupt`` exception will be delayed until the I/O completes and control returns to the Python interpreter (this may never happen if you use an infinite timeout). A no-op implementation is provided on non-Win32 systems to avoid the application from having to conditionally use it. Example usage: .. sourcecode:: python def stop_my_application(): # ... with allow_interrupt(stop_my_application): # main polling loop. In a typical ZMQ application, you would use the "self pipe trick" to send message to a ``PAIR`` socket in order to interrupt your blocking socket polling operation. In a Tornado event loop, you can use the ``IOLoop.stop`` method to unblock your I/O loop. c C s | j | � d S( s Translate ``action`` into a CTRL-C handler. ``action`` is a callable that takes no arguments and returns no value (returned value is ignored). It must *NEVER* raise an exception. If unspecified, a no-op will be used. N( t _init_action( t selft action( ( s5 /usr/lib64/python2.7/site-packages/zmq/utils/win32.pyt __init__>