<dt><i class="arg">direction</i></dt>
<dd><p>Direction is either <b class="const">Sent</b> or <b class="const">Received</b>.</p></dd>
<dt><i class="arg">version</i></dt>
<dd><p>Version is the protocol version.</p></dd>
<dt><i class="arg">content_type</i></dt>
<dd><p>Content type is the message content type.</p></dd>
<dt><i class="arg">message</i></dt>
<dd><p>Message is more info from the <b class="const">SSL_trace</b> API.
This argument is new for TclTLS 1.8.</p></dd>
</dl></dd>
<dt><b class="option">session</b> <i class="arg">channelId session_id session_ticket lifetime</i></dt>
<dd><p>This form of callback is invoked by the OpenSSL function
<b class="function">SSL_CTX_sess_set_new_cb()</b> whenever a new session id is sent by the
server during the initial connection and handshake and also during the session
if the <b class="option">-post_handshake</b> option is set to true. This callback is new for
TclTLS 1.8. The arguments are:</p>
<dl class="doctools_definitions">
<dt><i class="arg">session_id</i></dt>
<dd><p>Session Id is the current session identifier</p></dd>
<dt><i class="arg">session_ticket</i></dt>
<dd><p>Ticket is the session ticket info</p></dd>
<dt><i class="arg">lifetime</i></dt>
<dd><p>Lifetime is the ticket lifetime in seconds.</p></dd>
</dl></dd>
<dt><b class="option">verify</b> <i class="arg">channelId depth cert status error</i></dt>
<dd><p>This callback was moved to the <b class="option">-verify_callback</b> in TclTLS 1.8.</p></dd>
</dl>
</div>
<div id="subsection4" class="doctools_subsection"><h3><a name="subsection4">Values for Password Callback</a></h3>
<p>The callback for the <b class="option">-password</b> option is invoked by TclTLS whenever OpenSSL needs
to obtain a password. See below for the possible arguments passed to the
callback script. The user provided password is expected to be returned by the
callback.</p>

<b class="option">-validatecommand</b> option is set to <b class="cmd">tls::validate_command</b>.</p>
<p><em>The use of the variable <b class="variable">tls::debug</b> is not recommended.
It may be removed from future releases.</em></p>
</div>
<div id="section6" class="doctools_section"><h2><a name="section6">Debug Examples</a></h2>
<p>These examples use the default Unix platform SSL certificates. For standard
installations, -cadir and -cafile should not be needed. If your certificates
are in non-standard locations, update -cadir or use -cafile as needed.</p>
<p>Example #1: Use HTTP package</p>
<pre class="doctools_example">
package require http
package require tls
set url &quot;https://www.tcl.tk/&quot;
http::register https 443 [list ::tls::socket -autoservername true -require true -cadir /etc/ssl/certs  -command ::tls::callback -password ::tls::password -validatecommand ::tls::validate_command]
# Check for error
set token [http::geturl $url]
if {[http::status $token] ne &quot;ok&quot;} {
    puts [format &quot;Error %s&quot; [http::status $token]]
}
# Get web page
set data [http::data $token]
puts [string length $data]
# Cleanup
::http::cleanup $token
</pre>
<p>Example #2: Use raw socket</p>
<pre class="doctools_example">
package require tls
set url &quot;www.tcl-lang.org&quot;
set port 443
set ch [tls::socket -autoservername 1 -servername $url -request 1 -require 1  -alpn {http/1.1} -cadir /etc/ssl/certs -command ::tls::callback  -password ::tls::password -validatecommand ::tls::validate_command $url $port]
chan configure $ch -buffersize 65536
tls::handshake $ch
puts $ch &quot;GET / HTTP/1.1&quot;
flush $ch
after 500
set data [read $ch]
array set status [tls::status $ch]

installations, -cadir and -cafile should not be needed. If your certificates
are in non-standard locations, set -cadir or use -cafile as needed.</p>
<p>Example #3: Get web page</p>
<pre class="doctools_example">
package require http
package require tls
set url &quot;https://www.tcl.tk/&quot;
http::register https 443 [list ::tls::socket -autoservername true -require true -cadir /etc/ssl/certs]
# Check for error
set token [http::geturl $url]
if {[http::status $token] ne &quot;ok&quot;} {
    puts [format &quot;Error %s&quot; [http::status $token]]
}
# Get web page
set data [http::data $token]
puts $data
# Cleanup
::http::cleanup $token
</pre>
<p>Example #4: Download file</p>
<pre class="doctools_example">
package require http
package require tls
set url &quot;https://wiki.tcl-lang.org/sitemap.xml&quot;
set filename [file tail $url]
http::register https 443 [list ::tls::socket -autoservername true -require true -cadir /etc/ssl/certs]
# Get file
set ch [open $filename wb]
set token [::http::geturl $url -blocksize 65536 -channel $ch]
# Cleanup
close $ch
::http::cleanup $token
</pre>