Synnefo » snf-ganeti

def IsPidFileAlive(pidfile):

  """Check whether the given pidfile points to a live process.

    @param pidfile: Path to a file containing the pid to be checked

    @type  pidfile: string (filename)

  """

  try:

    pf = open(pidfile, 'r')

  except EnvironmentError, open_err:

    if open_err.errno == errno.ENOENT:

      return False

    else:

      raise errors.GenericError("Cannot open file %s. Error: %s" %

                                (pidfile, str(open_err)))

  try:

    pid = int(pf.read())

  except ValueError:

    raise errors.GenericError("Invalid pid string in %s" %

                              (pidfile,))

  return IsProcessAlive(pid)