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socket(+Domain, +Type, ?Stream)
Creates a socket of a given type and domain and associates a stream with
it.
- +Domain
- Atom
- +Type
- Atom
- ?Stream
- Atom, structure or variable.
Description
socket/3 is a direct link to the socket(2) system call, available on
Berkeley systems. Domain is either unix or internet, type is stream or
datagram. It creates a socket of the given type in the given domain and
creates a stream associated with it. After the connection is
established using bind/2, connect/2, listen/2 and/or accept/3, the
stream can be used for input and output to communicate with other
processes.
The unix domain can be used for communication between processes on the
same machine, whereas the internet domain can connect any two machines.
The stream type supports point-to-point reliable communication, whereas
the datagram communication is a network-type communication with clear
message boundaries, which, however, are not visible in ECLiPSe .
Note that in order to read data using read/1,2, it must have been
written in Prolog term format (i.e. ended with a period and a blank
space character). The output to sockets is buffered, so that data might
be actually written only after a call to flush(Stream).
When instantiated, Stream must be the symbolic stream name (atom). The
stream can also be specified as sigio(Stream). In this case the socket
is created and in addition it is instructed to send the signal io each
time new data appears in it.
Fail Conditions
None.
Resatisfiable
No.
Exceptions
- (5) type error
- Stream is instantiated, but not to an atom or a sigio structure.
- (5) type error
- Domain or Type are instantiated but not to atoms.
- (6) out of range
- Domain or Type are atoms, but different from the accepted ones.
- (170) system interface error
- It was not possible to create the socket.
Examples
Success:
socket(unix, stream, s).
socket(internet, datagram, socket).
Error:
socket(unix, stream, 1) (Error 5).
socket(telnet, datagram, X) (Error 6).
See Also
bind / 2, listen / 2, accept / 3, connect / 2, new_socket_server / 3, pipe / 2, exec / 2