example, don't use @samp{mkdir -p}, convenient as it may be, because
most systems don't support it.
+It is a good idea to avoid creating symbolic links in makefiles, since a
+few systems don't support them.
+
The Makefile rules for building and installation can also use compilers
and related programs, but should do so via @code{make} variables so that the
user can substitute alternatives. Here are some of the programs we
example, don't use @samp{mkdir -p}, convenient as it may be, because
most systems don't support it.
+It is a good idea to avoid creating symbolic links in makefiles, since a
+few systems don't support them.
+
The Makefile rules for building and installation can also use compilers
and related programs, but should do so via @code{make} variables so that the
user can substitute alternatives. Here are some of the programs we