doompanning/docs/man/nng_http_client_connect.3http.adoc
oxmox 17f68cf8fe Squashed 'external/nng/' content from commit 169221da
git-subtree-dir: external/nng
git-subtree-split: 169221da8d53b2ca4fda76f894bee8505887a7c6
2023-02-03 21:18:59 +01:00

98 lines
2.8 KiB
Text

= nng_http_client_connect(3http)
//
// 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_http_client_connect - establish HTTP client connection
== SYNOPSIS
[source, c]
----
#include <nng/nng.h>
#include <nng/supplemental/http/http.h>
void nng_http_client_connect(nng_http_client *client, nng_aio *aio);
----
== DESCRIPTION
The `nng_http_client_connect()` starts the process of establishing an HTTP
connection from _client_ to the server that was indicated in the URL that
_client_ was configured with.
The result of the operation will be stored in the _aio_ when the operation
is complete, and will be obtainable via
xref:nng_aio_result.3.adoc[`nng_aio_result()`].
On success, a pointer to the underlying HTTP client (type `nng_http_conn *`)
will be stored in the first output result of the _aio_, and can be
obtained by
xref:nng_aio_get_output.3.adoc[`nng_aio_get_output()`] with an _index_ of zero (0).
== RETURN VALUES
None.
== ERRORS
[horizontal]
`NNG_EADDRINVAL`:: The client is configured with an invalid address.
`NNG_ECANCELED`:: The operation was aborted.
`NNG_ECONNREFUSED`:: The TCP connection was refused by the server.
`NNG_ECONNRESET`:: The TCP connection was reset by the server.
`NNG_ENOMEM`:: Insufficient free memory exists.
== EXAMPLE
[source, c]
----
nng_aio *aio;
nng_url *url;
nng_http_client *client;
nng_http_conn *conn;
int rv;
// Error checks elided for clarity.
nng_url_parse(&url, "http://www.google.com");
nng_aio_alloc(&aio, NULL, NULL);
nng_http_client_alloc(&client, url);
nng_http_client_connect(client, aio);
// Wait for connection to establish (or attempt to fail).
nng_aio_wait(aio);
if ((rv = nng_aio_result(aio)) != 0) {
printf("Connection failed: %s\n", nng_strerror(rv));
} else {
// Connection established, get it.
conn = nng_aio_get_output(aio, 0);
// ... do something with it here
// Close the connection when done to avoid leaking it.
nng_http_conn_close(conn);
}
----
== SEE ALSO
[.text-left]
xref:nng_aio_get_output.3.adoc[nng_aio_get_output(3)],
xref:nng_aio_result.3.adoc[nng_aio_result(3)],
xref:nng_aio_wait.3.adoc[nng_aio_wait(3)],
xref:nng_strerror.3.adoc[nng_strerror(3)],
xref:nng_http_client_alloc.3http.adoc[nng_http_client_alloc(3http)],
xref:nng_http_conn_close.3http.adoc[nng_http_conn_close(3http)],
xref:nng_http_conn_read.3http.adoc[nng_http_conn_read(3http)],
xref:nng_http_conn_write.3http.adoc[nng_http_conn_write(3http)],
xref:nng.7.adoc[nng(7)]