Socket address family

The address family parameter on a socket() determines the format of the address structure to use on socket functions.

Address family protocols provide the network transportation of application data from one application to another (or from one process to another within the same machine). The application specifies the network transport provider on the protocol parameter of the socket.

The address family parameter (address_family) on the socket() function specifies the address structure that is used on the socket functions.

AF_INET address family
This address family provides interprocess communications between processes that run on the same system or on different systems.
AF_INET6 address family
This address family provides support for the Internet Protocol version 6 (IPv6). AF_INET6 address family uses a 128 bit (16 byte) address.
AF_UNIX address family
This address family provides interprocess communications on the same system that uses the socket APIs. The address is really a path name to an entry in the file system.
AF_UNIX_CCSID address family
The AF_UNIX_CCSID family is compatible with the AF_UNIX address family and has the same limitations.

Parent topic: Socket characteristics