Merge branch 'master' into master

src/module.c

@@ -29,6 +29,8 @@ int DoCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
                 RedisModuleString *ret = RedisModule_CreateString(ctx, output, strlen(output));
                 RedisModule_ReplyWithString(ctx, ret);
                 pclose(fp);
+        } else {
+                return RedisModule_WrongArity(ctx);
         }
         return REDISMODULE_OK;
 }