Fixed deprecated error librdkafka function

Author: accelerated

README.md

@@ -76,9 +76,15 @@ If you have installed _librdkafka_ on a non standard directory, you can use the
 cmake .. -DRDKAFKA_ROOT_DIR=/some/other/dir
 ```
 
-Note that finding _librdkafka_ will succeed iff there's an _include_ and _lib_
-directories inside the specified path, including both the _rdkafka.h_ header
-and the _librdkafka_ library file.
+Note that the **RDKAFKA_ROOT_DIR** must contain the following structure:
+
+```Shell
+${RDKAFKA_ROOT_DIR}/
+                   |
+                   + include/librdkafka/rdkafka.h
+                   |
+                   + lib/librdkafka.a
+```
 
 ---
 

src/kafka_handle_base.cpp

@@ -172,7 +172,7 @@ void KafkaHandleBase::set_handle(rd_kafka_t* handle) {
 Topic KafkaHandleBase::get_topic(const string& name, rd_kafka_topic_conf_t* conf) {
     rd_kafka_topic_t* topic = rd_kafka_topic_new(get_handle(), name.data(), conf);
     if (!topic) {
-        throw HandleException(rd_kafka_errno2err(errno));
+        throw HandleException(rd_kafka_last_error());
     }
     return Topic(topic);
 }