Hi, The Makefile contains a section called `check_now`. It references the files `zone1970.tab` and `zonenow.tab`. Other sections of the Makefile take account of the variable $ZONETABLES before using/checking zone files. Would it be possible to alter Makefile so it only runs check_now if at least one of zone1970/zonenow are in $ZONETABLES ? eg. something like this (now 100% sure this is the right logic...): check_now: checknow.awk date tzdata.zi zdump zic zone1970.tab zonenow.tab for tab in $(ZONETABLES); do \ rm -fr $@.dir mkdir $@.dir ./zic -d $@.dir tzdata.zi now=$(CHECK_NOW_TIMESTAMP) && \ future=`expr $(CHECK_NOW_FUTURE_SECS) + $$now` && \ ./zdump -i -t $$now,$$future \ $$(find $$PWD/$@.dir/????*/ -type f) \ >$@.dir/zdump.tab $(AWK) \ -v zdump_table=$@.dir/zdump.tab \ -f checknow.awk zonenow.tab rm -fr $@.dir done touch $@ thanks Stephen