= nng_http_conn_write_res(3)
:doctype: manpage
:manmanual: nng
:mansource: nng
:manvolnum: 3
:copyright: Copyright 2018 mailto:info@staysail.tech[Staysail Systems, Inc.] + \
            Copyright 2018 mailto:info@capitar.com[Capitar IT Group BV] + \
            {blank} + \
            This document is supplied under the terms of the \
            https://opensource.org/licenses/MIT[MIT License].

== NAME

nng_http_conn_write_res - write HTTP response

== SYNOPSIS

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

void nng_http_conn_write_res(nng_http_conn *conn, nng_http_res *res,
    nng_aio *aio);
-----------

== DESCRIPTION

The `nng_http_conn_write_res()` function starts an asynchronous write of
the HTTP response _res_ to the connection _conn_.  The entire response is sent,
including headers, and if present, the response body data.  (The
response body can be set with
<<nng_http_res_set_data#,nng_http_res_set_data>> or
<<nng_http_res_copy_data#,nng_http_res_copy_data>>.)

This function returns immediately, with no return value.  Completion of
the operation is signaled via the _aio_, and the final result may be
obtained via <<nng_aio_result#,nng_aio_result>>. That result will
either be zero or an error code.

=== Persistent Connections

By default, for `HTTP/1.1` connections, the connection is kept open, and
will be reused to receive new requests.

If however the _res_ contains a header of `Connection:` with a value 
of `Close` (case-insensitive) or the response corresponds to `HTTP/1.0`,
then the connection is immediately after sending the response.

== RETURN VALUES

None.

== ERRORS

`NNG_ECANCELED`:: The operation was canceled.
`NNG_ECLOSED`:: The connection was closed.
`NNG_ECONNRESET`:: The peer closed the connection.
`NNG_ENOMEM`:: Insufficient free memory to perform the operation.
`NNG_ENOTSUP`:: HTTP operations are not supported.
`NNG_ETIMEDOUT`:: Timeout waiting for data from the connection.

== SEE ALSO

<<nng_aio_alloc#,nng_aio_alloc(3)>>,
<<nng_aio_result#,nng_aio_result(3)>>,
<<nng_http_alloc_handler#,nng_http_alloc_handler(3)>>,
<<nng_http_client_connect#,nng_http_client_connect(3)>>,
<<nng_http_conn_read_all#,nng_http_conn_read_all(3)>>,
<<nng_strerror#,nng_strerror(3)>>,
<<nng#,nng(7)>>

== COPYRIGHT

{copyright}