make set-version-recursor complain if invoked incorrectly

diff --git a/build-scripts/set-version-recursor b/build-scripts/set-version-recursor
index 621e0489668be1118715a92bf2d4f0914f7d2f0b..e0e00c78c0696993ea1d2ed444d5071ac402fdb1 100755 (executable)
--- a/build-scripts/set-version-recursor
+++ b/build-scripts/set-version-recursor
@@ -1,4 +1,7 @@
 #!/usr/bin/env bash
+
+if [ "$#" -ne "3" ] ; then echo "Syntax: set-version-recursor VERSION DEB_VERSION RPM_VERSION"; exit ; fi
+
 VERSION=$1
 DEB_VERSION=$2
 RPM_VERSION=$3