careful, don't give the source file that ext, or the file will be
overwritten.
+If you use @code{--outdir}, you should also @code{cd} to that directory
+before running LaTeX or makeinfo.
+
@strong{[UGH: IS THIS THE BEST WAY TO DO IT. MAYBE ADD A COMMENT LINE TO THE
GENERATED FILE, SO MUDELA-BOOK CAN TEST IF THE FILE IT IS TO OVERWRITE
IS GENERATED.]}