= nng_socket(5)
|
//
|
// Copyright 2018 Staysail Systems, Inc. <info@staysail.tech>
|
// Copyright 2018 Capitar IT Group BV <info@capitar.com>
|
//
|
// This document is supplied under the terms of the MIT License, a
|
// copy of which should be located in the distribution where this
|
// file was obtained (LICENSE.txt). A copy of the license may also be
|
// found online at https://opensource.org/licenses/MIT.
|
//
|
|
== NAME
|
|
nng_socket - socket handle
|
|
== SYNOPSIS
|
|
[source, c]
|
----
|
#include <nng/nng.h>
|
|
typedef struct nng_socket_s nng_socket;
|
----
|
|
== DESCRIPTION
|
|
An `nng_socket`(((socket))) is a handle to an underlying socket object.
|
All communication between the application and remote Scalability Protocol
|
peers is done through sockets.
|
A given socket can have multiple dialers (xref:nng_dialer.5.adoc[`nng_dialer`])
|
and/or listeners (xref:nng_listener.5.adoc[`nng_listener`]), and multiple
|
pipes (xref:nng_pipe.5.adoc[`nng_pipe`]), and
|
may be connected to multiple transports at the same time.
|
However, a given socket will have exactly one protocol associated with it,
|
and is responsible for any state machines or other protocol-specific logic.
|
|
IMPORTANT: The `nng_socket` structure is always passed by value (both
|
for input parameters and return values), and should be treated opaquely.
|
Passing structures this way gives the compiler a chance to perform
|
accurate type checks in functions passing values of this type.
|
|
Each `nng_socket` is created by a protocol-specific constructor, such as
|
xref:nng_rep_open.3.adoc[`nng_rep_open()`].
|
When the socket is no longer needed, it can be closed with
|
xref:nng_close.3.adoc[`nng_close()`].
|
|
[[NNG_SOCKET_INITIALIZER]]
|
=== Initialization
|
|
A socket may be initialized using the macro `NNG_SOCKET_INITIALIZER`
|
before it is opened, to prevent confusion with valid open sockets.
|
|
For example:
|
|
[source, c]
|
----
|
nng_socket s = NNG_SOCKET_INITIALIZER;
|
----
|
|
== SEE ALSO
|
|
[.text-left]
|
xref:libnng.3.adoc[libnng(3)],
|
xref:nng_close.3.adoc[nng_close(3)],
|
xref:nng_getopt.3.adoc[nng_getopt(3)],
|
xref:nng_setopt.3.adoc[nng_setopt(3)],
|
xref:nng_socket_id.3.adoc[nng_socket_id(3)],
|
xref:nng_dialer.5.adoc[nng_dialer(5)],
|
xref:nng_listener.5.adoc[nng_listener(5)],
|
xref:nng_options.5.adoc[nng_options(5)],
|
xref:nng.7.adoc[nng(7)]
|
