= nng_stream_set(3str)
//
// Copyright 2018 Staysail Systems, Inc. <info@staysail.tech>
// Copyright 2018 Capitar IT Group BV <info@capitar.com>
// Copyright 2019 Devolutions <info@devolutions.net>
//
// 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_stream_set - set option on byte stream

== SYNOPSIS

[source, c]
----
#include <nng/nng.h>

int nng_stream_set(nng_stream *s, const char *name, const void *data, size_t size);

int nng_stream_set_bool(nng_stream *s, const char *opt, bool val);

int nng_stream_set_int(nng_stream *s, const char *opt, int val);

int nng_stream_set_ms(nng_stream *s, const char *opt, nng_duration val);

int nng_stream_set_ptr(nng_stream *s, const char *opt, void *val);

int nng_stream_set_size(nng_stream *s, const char *opt, size_t val);

int nng_stream_set_string(nng_stream *s, const char *opt, const char *val);

int nng_stream_set_uint64(nng_stream *s, const char *opt, uint64_t val);

int nng_stream_set_addr(nng_stream *s, const char *opt, const nng_sockaddr *val);

----

== DESCRIPTION

The `nng_stream_set()` functions are used to configure options for the
xref:nng_stream.5.adoc[byte stream] _s_.
The actual options that may be configured in this way vary, and are
specified by _opt_.
A number of them are documented in
xref:nng_options.5.adoc[nng_options(5)].

Additionally some transport-specific and protocol-specific options are
documented with the transports and protocols themselves.

=== Forms

The details of the type, size, and semantics of the option will depend
on the actual option, and will be documented with the option itself.

`nng_stream_set()`::
This function is untyped, and can be used to configure any arbitrary data.
The _val_ pointer addresses the data to copy, and _size_ is the
size of the objected located at _val_.
+
TIP: It may be easier to use one of the typed forms of this function.

`nng_stream_set_bool()`::
This function is for options which take a Boolean (`bool`).

`nng_stream_set_int()`::
This function is for options which take an integer (`int`).

`nng_stream_set_ms()`::
This function is used to configure time durations (such as timeouts) using
the type
xref:nng_duration.5.adoc[`nng_duration`].
The duration is an integer number of milliseconds.

`nng_stream_set_ptr()`::
This function is used to pass a pointer to structured data.
The data referenced by is generally managed by other functions.
For example, TLS configuration objects created with
xref:nng_tls_config.3tls.adoc[`nng_tls_config_alloc()`]
can be passed this way.
+
NOTE: This form is somewhat special in that the object is generally
not copied, but instead the *pointer* to the object is copied.
Please see the documentation for the specific option for further details.

`nng_stream_set_size()`::
This function is used to configure a size, typically for buffer sizes,
message maximum sizes, and similar options.

`nng_stream_set_string()`::
This function is used to pass configure a string.
Strings passed this way must be legal UTF-8 or ASCII strings, terminated
with a `NUL` (`\0`) byte.
(Other constraints may apply as well, see the documentation for each option
for details.)

`nng_stream_set_uint64()`::
This function is used to configure a 64-bit unsigned value/
This is typically used for identifiers, network numbers,
and similar options.

`nng_stream_set_addr()`::
This function is used to configure a
xref:nng_sockaddr.5.adoc[socket address].
The value is copied, and thus the caller may discard the supplied
value immediately after this function returns.

== RETURN VALUES

This function returns 0 on success, and non-zero otherwise.

== ERRORS

[horizontal]
`NNG_ECLOSED`:: The connection is closed.
`NNG_EINVAL`:: Either _data_ or _size_ are invalid.
`NNG_ENOTSUP`:: The option is not supported.
`NNG_EREADONLY`:: The option may not be modified.

== SEE ALSO

[.text-left]
xref:nng_strerror.3.adoc[nng_strerror(3)],
xref:nng_stream_get.3str.adoc[nng_stream_get(3str)],
xref:nng_options.5.adoc[nng_options(5)],
xref:nng_ipc_options.5.adoc[nng_ipc_options(5)],
xref:nng_tcp_options.5.adoc[nng_tcp_options(5)],
xref:nng_tls_options.5.adoc[nng_tls_options(5)],
xref:nng_stream.5.adoc[nng_stream(5)]