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The Socket Library


In operating systems, the software performing all the tasks and protocols described above is usually part of the kernel, and so it is in . The programming interface most common in the world is the Berkeley Socket Library. Its name derives from a popular analogy that views ports as sockets, and connecting to a port as plugging in. It provides the (bind(2)) call to specifiy a remote host, a transport protocol, and a service which a program can connect or listen to (using connect(2), listen(2), and accept(2)). The socket library is however somewhat more general, in that it provides not only a class of TCP/IP-based sockets (the AF_INET sockets), but also a class that handles connections local to the machine (the AF_UNIX class). Some implementations can also handle other classes as well, like the XNS (Xerox Networking System) protocol, or X.25.

In , the socket library is part of the standard libc C library. Currently, it only supports AF_INET and AF_UNIX sockets, but efforts are made to incorporate support for Novell's networking protocols, so that eventually one or more socket classes for these would be added.


root (Andrea Pellizzon)
Thu Oct 19 10:26:44 MET 1995