diff --git a/ncurses.spec b/ncurses.spec
index cfd5877..e65f32d 100644
--- a/ncurses.spec
+++ b/ncurses.spec
@@ -31,7 +31,7 @@
 %global soname_tinfo tinfow
 %endif
 
-%define patchlvl %(%{_sourcedir}/get_version_number.sh %{_sourcedir})
+%define patchlvl %(bash %{_sourcedir}/get_version_number.sh %{_sourcedir})
 %define basevers 6.2
 
 Name:           ncurses