The CLIM-SYS package contains useful, "system-like" utilities such as resources and multi-processing primitives. These utilities are neither part of Common Lisp nor conceptually within the province of CLIM itself.
All of the symbols documented in this appendix are accessible as external symbols in the CLIM-SYS package.
Common Lisp Interface Manager 2.0 User's Guide - 20 Sep 2011