ATTACH process_name
           /PARENT

    Switches control of your terminal from your current process to
    another process in your job.  Specify the target process with
    the process_name parameter.

Additional information available:

/PARENT

    This qualifier specifies that control of your terminal is to switched
    to the process that is the parent process to your current process.
    If this qualifier is specified, do not specify the process_name
    parameter in the ATTACH command.