Improve ac_converter to print a help message.
# See the License for the specific language governing permissions and
# limitations under the License.
-"""This script reads config.h.meson, looks for header
+help_message = """Usage: %s <config.h.meson>
+
+This script reads config.h.meson, looks for header
checks and writes the corresponding meson declaration.
Copy config.h.in to config.h.meson, replace #undef
@@ -364,6 +366,11 @@ function_data = \
headers = []
functions = []
sizes = []
+
+if len(sys.argv) != 2:
+ print(help_message % sys.argv[0])
+ sys.exit(0)
+
with open(sys.argv[1]) as f:
for line in f:
line = line.strip()
