= gun:open(3)
== Name
gun:open - Open a connection to the given host and port
== Description
[source,erlang]
----
open(Host, Port) -> open(Host, Port, #{})
open(Host, Port, Opts) -> {ok, pid()} | {error, Reason}
Host :: inet:hostname() | inet:ip_address()
Port :: inet:port_number()
Opts :: gun:opts()
Reason :: {options, OptName}
| {options, {http | http2 | socks | ws, OptName}}
| any()
OptName :: atom()
----
Open a connection to the given host and port.
== Arguments
Host::
Host or IP address to connect to.
Port::
Port to connect to.
Opts::
Options for this connection.
== Return value
The pid of the newly created Gun process is returned.
Note that this does not indicate that the connection
has been successfully opened; the link:man:gun_up(3)[gun_up(3)]
message will be sent for that.
== Changelog
* *1.0*: Function introduced.
== Examples
.Connect to a server
[source,erlang]
----
{ok, ConnPid} = gun:open("example.org", 443).
----
.Connect to a server with custom options
[source,erlang]
----
{ok, ConnPid} = gun:open("example.org", 443,
#{protocols => [http2]}).
----
.Connect to a server using its IP address
[source,erlang]
----
{ok, ConnPid} = gun:open({127,0,0,1}, 443).
----
== See also
link:man:gun(3)[gun(3)],
link:man:gun:open_unix(3)[gun:open_unix(3)],
link:man:gun:await_up(3)[gun:await_up(3)],
link:man:gun_tunnel_up(3)[gun_tunnel_up(3)],
link:man:gun_up(3)[gun_up(3)]
