This was over-engineered, and only one of the three rules which
create .html files depends on both the header and the footer.
# web
html := $(addprefix web/, $(addsuffix .html, \
index lopsub-api lopsubgen.1 lopsubex.1 $(m4_man_pages:.gz=)))
-$(html): $(addprefix web/, $(addsuffix .html, header footer))
-
www: $(html)
-
-web/lopsub-api.html: lopsub.h.m4
+web/lopsub-api.html: lopsub.h.m4 web/header.html web/footer.html
$(M4) -DOUTPUT_MODE=HTML web/header.html $(gendoc) \
$< web/footer.html > $@
web/index.html: web/lopsub.7.html
$(LN) -s $(notdir $<) $@
-web/%.html: %.gz
+web/%.html: %.gz web/header.html
$(CP) web/header.html $@
$(ZCAT) $< | $(GROFF) -m man -Thtml | sed -e '1,/^<body>/d' >> $@