clearer usage notes for cli

jcupitt · jcupitt · commit 739389d18d11 · 2017-09-04T16:16:45.000+01:00
see https://github.com/jcupitt/libvips/issues/725
diff --git a/libvips/iofuncs/operation.c b/libvips/iofuncs/operation.c
@@ -407,7 +407,7 @@ vips_operation_usage( VipsOperationClass *class, VipsBuf *buf )
 	vips_argument_class_map( object_class,
 		(VipsArgumentClassMapFn) vips_operation_class_usage_arg, 
 			buf, &usage );
-	vips_buf_appends( buf, "\n" );
+	vips_buf_appends( buf, " [--option-name option-value ...]\n" );
 
 	/* Show required types.
 	 */
