When discussing the standard macro packages in the context of
__USE_*__ macros, link to them as well as to the %use directive.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
\S{use_def} \I\c{__USE_*__}\c{__USE_}\e{package}\c{__}: Package
Include Test
-When a standard macro package is included with the \c{%use} directive
-(see \k{use}), a single-line macro of the form
+When a standard macro package (see \k{macropkg}) is included with the
+\c{%use} directive (see \k{use}), a single-line macro of the form
\c{__USE_}\e{package}\c{__} is automatically defined. This allows
testing if a particular package is invoked or not.