-
+/**
+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.
+*/
:- module(sockets, [socket_client_open/3,
socket_server_open/2,
socket_server_accept/4,
:- use_module(library(error)).
+%% 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_client_open(Addr, Stream, Options) :-
( var(Addr) ->
throw(error(instantiation_error, socket_client_open/3))
socket_client_open/3),
'$socket_client_open'(Address, Port, Stream, Alias, EOFAction, Reposition, Type).
-
+%% socket_server_open(+Addr, -ServerSocket).
+%
+% Open a server socket, returning a ServerSocket. Use that ServerSocket to accept incoming connections in
+% socket\_server\_accept/4. Addr must satisfy `Addr = Address:Port`. Depending on the operating system
+% configuration, some ports might be reserved for superusers.
socket_server_open(Addr, ServerSocket) :-
must_be(var, ServerSocket),
( ( integer(Addr) ; var(Addr) ) ->
'$socket_server_open'(Address, Port, ServerSocket)
).
-
+%% 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_accept(ServerSocket, Client, Stream, Options) :-
must_be(var, Client),
must_be(var, Stream),
socket_server_accept/4),
'$socket_server_accept'(ServerSocket, Client, Stream, Alias, EOFAction, Reposition, Type).
-
+%% socket_server_close(+ServerSocket).
+%
+% Stops listening on that ServerSocket. It's recommended to always close a ServerSocket once it's no longer needed
socket_server_close(ServerSocket) :-
'$socket_server_close'(ServerSocket).
-
+%% current_hostname(-HostName).
+%
+% Returns the current hostname of the computer in which Scryer Prolog is executing right now
current_hostname(HostName) :-
'$current_hostname'(HostName).