manpage build: fail early when xmlto is not available
When we try to build manpages with xmlto and sed, but xmlto is
missing fail at the xmlto stage. Otherwise, one may run `cd doc;
make' and miss the warnings like:
xmlto: not found
sed: hg.1: No such file or directory
and end up with empty files installed as manpages.
--- a/doc/Makefile Fri May 08 07:54:00 2009 +0200
+++ b/doc/Makefile Thu May 07 15:08:25 2009 +0300
@@ -20,8 +20,8 @@
${PYTHON} gendoc.py > $@
%: %.xml
- xmlto man $*.xml ; \
- sed -e 's/^\.hg/\\\&.hg/' $* > $*~ ; \
+ xmlto man $*.xml && \
+ sed -e 's/^\.hg/\\\&.hg/' $* > $*~ && \
mv $*~ $*
%.xml: %.txt