One of the attractions of multithreaded programming is I/O performance. The traditional UNIX API gave you little assistance in this area. You either used the facilities of the file system or bypassed the file system entirely.
This section shows how to use threads to get more flexibility through I/O concurrency and multibuffering. This section also discusses the differences and similarities between the approaches of synchronous I/O with threads, and asynchronous I/O with and without threads.