<dd><a href="#NAME">NAME</a> <dl>
            <dd><strong>tls</strong> - binding to <strong>OpenSSL</strong>
                toolkit.</dd>
        </dl>
    </dd>
    <dd><a href="#SYNOPSIS">SYNOPSIS</a> </dd>
    <dd><dl>
            <dd><b>package require Tcl </b><em>?8.2?</em></dd>
            <dd><b>package require tls </b><em>?1.5?</em></dd>
            <dt>&nbsp;</dt>
            <dd><b>tls::init </b><i>?options?</i> </dd>
            <dd><b>tls::socket </b><em>?options? host port</em></dd>
            <dd><b>tls::socket</b><em> ?-server command?
                ?options? port</em></dd>
            <dd><b>tls::handshake</b><em> channel</em></dd>
            <dd><b>tls::status </b><em>?-local? channel</em></dd>

<h3><a name="NAME">NAME</a></h3>

<p><strong>tls</strong> - binding to <strong>OpenSSL</strong>
toolkit.</p>

<h3><a name="SYNOPSIS">SYNOPSIS</a></h3>

<p><b>package require Tcl 8.2</b><br>
<b>package require tls 1.6</b><br>
<br>
<a href="#tls::init"><b>tls::init </b><i>?options?</i><br>
</a><a href="#tls::socket"><b>tls::socket </b><em>?options? host
port</em><br>
<b>tls::socket</b><em> ?-server command? ?options? port</em><br>
</a><a href="#tls::status"><b>tls::status </b><em>?-local? channel</em><br>

<p>This extension provides a generic binding to <a
href="http://www.openssl.org/">OpenSSL</a>, utilizing the
<strong>Tcl_StackChannel</strong>
API for Tcl 8.2 and higher. The sockets behave exactly the same
as channels created using Tcl's built-in <strong>socket</strong>
command with additional options for controlling the SSL session.
To use TLS with an earlier version of Tcl than 8.2, please obtain
TLS 1.3.  Please note that there are known limitations with the
stacked channel implementation prior to 8.3.2, so it is recommended
that TLS is used with an 8.3.2+ interpreter.  The current version
of TLS will work with Tcl 8.2+, it is just more stable with 8.3.2+.
</p>

<h3><a name="COMMANDS">COMMANDS</a></h3>

<p>Typically one would use the <strong>tls::socket </strong>command
which provides compatibility with the native Tcl <strong>socket</strong>
command. In such cases <strong>tls::import</strong> should not be

The use of the variable <strong>tls::debug</strong> is not recommended.
It may be removed from future releases.
</em>
</p>

<h3><a name="HTTPS EXAMPLE">HTTPS EXAMPLE</a></h3>

<p>This example requires a patch to the <strong>http</strong>
module that ships with Tcl - this patch has been submitted for
inclusion in Tcl 8.2.1, but is also provided in the tls directory
if needed. A sample server.pem is provided with the TLS release,
courtesy of the <strong>OpenSSL</strong> project.</p>

<pre><code>
package require http
package require tls

http::register https 443 [list ::tls::socket -require 1 -cafile ./server.pem]