When the LispWorks IDE starts it sets the follow variables:
mp:*background-standard-output*
.hcl:*background-output* is the default destination of cl:*standard-output*, cl:*trace-output* and cl:*error-output*.
hcl:*background-input* is the default source cl:*standard-input*.
hcl:*background-query-io* is the default for cl:*query-io* and cl:*debug-io*.
The output sent to mp:*background-standard-output*
can be viewed in the Output Browser tool and in the Output tab of Editor and Listener tools. See the entry for hcl:*background-output* in the LispWorks® User Guide and Reference Manual for more details.
LispWorks IDE User Guide (Windows version) - 01 Dec 2021 19:37:50