In Chapter 2, we looked at the basic I/O system calls in Linux. These calls form not only the basis of file I/O, but also the foundation of virtually all communication on Linux. In Chapter 3, we looked at how user-space buffering is often needed on top of the basic I/O system calls, and we studied a specific user-space buffering solution, Cís standard I/O library. In this chapter, weíll look at the more advanced I/O system calls that Linux provides:
Allows a single call to read or write data to and from many buffers at once; useful for bunching together fields of different data structures to form one I/O transaction.