Use 'bctest' script to test if bc works (as in the main branch).

	@./$(BNTEST) >tmp.bntest

	@echo quit >>tmp.bntest

	@echo "running bc"

	@bc tmp.bntest 2>&1 | $(PERL) -e 'while (<STDIN>) {if (/^test (.*)/) {print STDERR "\nverify $$1";} elsif (!/^0$$/) {die "\nFailed! bc: $$_";} print STDERR "."; $$i++;} print STDERR "\n$$i tests passed\n"'

	@<tmp.bntest sh -c "`sh ./bctest`" | $(PERL) -e '$$i=0; while (<STDIN>) {if (/^test (.*)/) {print STDERR "\nverify $$1";} elsif (!/^0$$/) {die "\nFailed! bc: $$_";} else {print STDERR "."; $$i++;}} print STDERR "\n$$i tests passed\n"'

	@echo 'test a^b%c implementations'

	./$(EXPTEST)