Scryer Prolog documentation

Module sockets

:- use_module(library(sockets)).

Predicates for handling network sockets, both as a server and as a client. As a server, you should open a socket an call socket_server_accept/4 to get a stream for each connection. As a client, you should just open a socket and you will receive a stream. In both cases, with a stream, you can use the usual predicates to read and write to the stream.

socket_client_open(+Addr, -Stream, +Options).

Open a socket to a server, returning a stream. Addr must satisfy Addr = Address:Port.

The following options are available:

  • alias(+Alias): Set an alias to the stream
  • eof_action(+Action): Defined what happens if the end of the stream is reached. Values: error, eof_code and reset.
  • reposition(+Boolean): Specifies whether repositioning is required for the stream. false is the default.
  • type(+Type): Type can be text or binary. Defines the type of the stream, if it's optimized for plain text or just binary

socket_server_open(+Addr, -ServerSocket).

Open a server socket, returning a ServerSocket. Use that ServerSocket to accept incoming connections in socket_server_accept/4. Addr must satisfy Addr = Address:Port. Depending on the operating system configuration, some ports might be reserved for superusers.

socket_server_accept(+ServerSocket, -Client, -Stream, +Options).

Given a ServerSocket and a list of Options, accepts a incoming connection, returning data from the Client and a Stream to read or write data.

The following options are available:

  • alias(+Alias): Set an alias to the stream
  • eof_action(+Action): Defined what happens if the end of the stream is reached. Values: error, eof_code and reset.
  • reposition(+Boolean): Specifies whether repositioning is required for the stream. false is the default.
  • type(+Type): Type can be text or binary. Defines the type of the stream, if it's optimized for plain text or just binary

socket_server_close(+ServerSocket).

Stops listening on that ServerSocket. It's recommended to always close a ServerSocket once it's no longer needed

current_hostname(-HostName).

Returns the current hostname of the computer in which Scryer Prolog is executing right now