The C Language API is the native programming interface for MySQL. In fact, virtually all the other APIs that are available use the C API. For example, the PHP interface, which you will learn about in Lesson 24, “Using MySQL with PHP,” is written in C using this API. It contains many functions that map directly to a corresponding function in the underlying C library.
The client utilities shipped with MySQL, such as mysql and mysqladmin, are all written using the C API. You can examine the source code for these if you want to see how they work.
The client library libmysqlclient.so contains the functions ...