You link the object files for RDBPRE RDO programs just as you
    would link any program object file. Invoke the OpenVMS Linker
    and specify one or more object file specifications and any link
    switches you want to use. The following example shows how to link
    all the modules of the program COB_SAMPLE.RCO:

    $ LINK COB_SAMPLE, COB_CALL_OTHER, COB_CALLABLE_ERROR_HANDLER