subprocess2.py 文件源码

def communicate(self, input=None, timeout=None, nag_timer=None,
                  nag_max=None):
    """Adds timeout and callbacks support.

    Returns (stdout, stderr) like subprocess.Popen().communicate().

    - The process will be killed after |timeout| seconds and returncode set to
      TIMED_OUT.
    - If the subprocess runs for |nag_timer| seconds without producing terminal
      output, print a warning to stderr.
    """
    self.timeout = timeout
    self.nag_timer = nag_timer
    self.nag_max = nag_max
    if (not self.timeout and not self.nag_timer and
        not self.stdout_cb and not self.stderr_cb):
      return super(Popen, self).communicate(input)

    if self.timeout and self.shell:
      raise TypeError(
          'Using timeout and shell simultaneously will cause a process leak '
          'since the shell will be killed instead of the child process.')

    stdout = None
    stderr = None
    # Convert to a lambda to workaround python's deadlock.
    # http://docs.python.org/library/subprocess.html#subprocess.Popen.wait
    # When the pipe fills up, it would deadlock this process.
    if self.stdout and not self.stdout_cb and not self.stdout_is_void:
      stdout = []
      self.stdout_cb = stdout.append
    if self.stderr and not self.stderr_cb and not self.stderr_is_void:
      stderr = []
      self.stderr_cb = stderr.append
    self._tee_threads(input)
    if stdout is not None:
      stdout = ''.join(stdout)
    if stderr is not None:
      stderr = ''.join(stderr)
    return (stdout, stderr)