def signalProcess(signalID):
    """
        Send a signal to the process.

        @param signalID: can be
          - one of C{"KILL"}, C{"TERM"}, or C{"INT"}.
              These will be implemented in a
              cross-platform manner, and so should be used
              if possible.
          - an integer, where it represents a POSIX
              signal ID.

        @raise twisted.internet.error.ProcessExitedAlready: If the process has
            already exited.
        @raise OSError: If the C{os.kill} call fails with an errno different
            from C{ESRCH}.
        """
