Unix sockets

Unix sockets provide a way to send data over network interfaces.

A socket connection has an address, composed of an IP address and a port. Computers can open multiple connections to and from the same addresses using different ports.

There are several functions used to manipulate sockets:

• socket: Creates an endpoint for communication and returns its associated file-descriptor.
• setsockopt: Set socket stream options.
• getsockopt: Get socket stream options.
• getsockname: Get the socket's associated name.

There are several functions used to manipulate network format numbers:

• inet_aton, inet_addr, inet_network: Interpret strings representing numbers in the internet standard '.' notation.
• inet_pton: Convert a presentation format address to network format.
• inet_aton: Interpret string as an internet address.
• inet_ntop: Convert an address from network format to presentation format.
• getprotobyname: Get a network protocol by name.
• gethostbyname: Get a network host's address from its hostname.