class_docstr: Event loop for posix systems (Linux, Mac os X).
docstr: Notify the event loop that SIGWINCH has been received
docstr_tok: ["Notify","the","event","loop","that","SIGWINCH","has","been","received"]
code: def received_winch(self):
      """
      Notify the event loop that SIGWINCH has been received
      """
      # Process signal asynchronously, because this handler can write to the
      # output, and doing this inside the signal handler causes easily
      # reentrant calls, giving runtime errors..
  
      # Furthur, this has to be thread safe. When the CommandLineInterface
      # runs not in the main thread, this function still has to be called
      # from the main thread. (The only place where we can install signal
      # handlers.)
      def process_winch():
          if self._callbacks:
              self._callbacks.terminal_size_changed()
  
      self.call_from_executor(process_winch)
  
imports: from __future__ import unicode_literals
  import fcntl
  import os
  import signal
  import threading
  import time
  from prompt_toolkit.terminal.vt100_input import InputStream
  from prompt_toolkit.utils import DummyContext, in_main_thread
  from prompt_toolkit.input import Input
  from .base import EventLoop, INPUT_TIMEOUT
  from .callbacks import EventLoopCallbacks
  from .inputhook import InputHookContext
  from .posix_utils import PosixStdinReader
  from .utils import TimeIt
  from .select import AutoSelector, Selector, fd_to_int
label_desc: Use image node_id 4 for calling the PosixEventLoop obj's underlying member method code with example usage: obj.received_winch() without return types