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= gun:head(3)

== Name

gun:head - Get headers of a resource representation

== Description

[source,erlang]
----
head(ConnPid, Path)
    -> head(ConnPid, Path, [], #{}).

head(ConnPid, Path, Headers)
    -> head(ConnPid, Path, Headers, #{})

head(ConnPid, Path, Headers, ReqOpts)
    -> StreamRef

ConnPid   :: pid()
Path      :: iodata()
Headers   :: gun:req_headers()
ReqOpts   :: gun:req_opts()
StreamRef :: gun:stream_ref()
----

Get headers of a resource representation.

This function performs the same operation as
link:man:gun:get(3)[gun:get(3)], except the server will not
send the resource representation, only the response's status
code and headers.

While servers are supposed to send the same headers as for
a GET request, they sometimes will not. For example the
`content-length` header may be dropped from the response.

== Arguments

ConnPid::

The pid of the Gun connection process.

Path::

Path to the resource.

Headers::

Additional request headers.

ReqOpts::

Request options.

== Return value

A reference that identifies the newly created stream is
returned. It is this reference that must be passed in
subsequent calls and will be received in messages related
to this new stream.

== Changelog

* *1.0*: Function introduced.

== Examples

.Get headers of a resource representation
[source,erlang]
----
StreamRef = gun:head(ConnPid, "/articles", [
    {<<"accept">>, <<"text/html;q=1.0, application/xml;q=0.1">>}
]).
----

.Get headers of a resource representation with request options
[source,erlang]
----
StreamRef = gun:head(ConnPid, "/articles", [], #{
    reply_to => ReplyToPid
}).
----

== See also

link:man:gun(3)[gun(3)],
link:man:gun:get(3)[gun:head(3)],
link:man:gun:await(3)[gun:await(3)],
link:man:gun_push(3)[gun_push(3)],
link:man:gun_inform(3)[gun_inform(3)],
link:man:gun_response(3)[gun_response(3)]