Sockets are a method of IPC that allow data to be exchanged between applications, either on the same host (computer) or on different hosts connected by a network. The first widespread implementation of the sockets API appeared with 4.2BSD in 1983, and this API has been ported to virtually every UNIX implementation, as well as most other operating systems.
The sockets API is formally specified in POSIX.1g, which was ratified in 2000 after spending about a decade as a draft standard. This standard has been superseded by SUSv3.
This chapter and the following chapters describe the use of sockets, as follows:
This chapter provides a general introduction to the sockets API. The following chapters assume an understanding ...