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accept(+Stream, -From, ?NewStream)
Accepts a connection for a stream socket and creates a new socket which can
be used for I/O.
- Stream handle or alias (atom)
- A term unifiable with a structure atom/integer.
- Atom, structure or variable.
accept/3 is a direct link to the accept(2) socket system call.
Stream must be a socket stream created with socket/3 or new_socket_server/3
of the type stream, listening for connections. accept/3 blocks until
there is a connection request from another process, and then it creates
a new socket stream NewStream with the same properties as Stream, which
can be then used for communication with the connecting process. The
Stream socket remains open and listening for further connections.
In the internet domain, From is unified with the address of the
connecting process in the form HostName/Port. In the unix domain, From
is unified with an empty atom ''.
When instantiated, NewStream must be a symbolic stream name, i.e. an
atom. The stream can also be specified as sigio(NewStream). 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.
Stream sockets are connected using the standard sequence, i.e.
socket/3, bind/2, listen/2 and accept/3 on the server and socket/3 and
connect/2 on the client. After the sockets are connected, both
processes can use them for reading and writing.
Modes and Determinism
- accept(+, -, -) is det
- accept(+, -, +) is det
- (4) instantiation fault
- Stream is not instantiated.
- (5) type error
- Stream is instantiated, but not to an atom or a sigio/1 structure.
- (5) type error
- From is instantiated but not to an atom or a structure.
- (170) system interface error
- It was not possible to execute the system call.
socket(internet, stream, s), bind(s, Addr), listen(s, 1),
accept(s, From, news).
accept(s, From, 6) (Error 5).
socket(internet, datagram, s), bind(s, Addr), listen(s, 2),
accept(s, From, news) (Error 170).
socket / 3, bind / 2, listen / 2, connect / 2