This script will send the current external IP of the sending machine to a given email address. To use it, call ::mailip::sendip [email protected].

It assumes, that you have a running SMTP sever on your connected machine.

 # mailip.tcl
 package require http
 package require tdom
 package require smtp

 namespace eval mailip {
        # Setup here...
        variable SMTPSERVER localhost
        variable SENDER [email protected] ;# We need a valid sender address

 proc ::mailip::getip {} {
        # Returns your current external IP
        # or
        set result
        set request [::http::geturl]
        set answer [::http::data $request]
        set adom [::dom parse -html $answer]
        set domdoc [$adom documentElement]
        set body [[lindex [$domdoc getElementsByTagName body] 0] text]
        set result [string trim [lindex [split $body :] 1]]
        return $result

 proc ::mailip::sendip {to} {
        set msg [::mime::initialize -canonical text/plain -string "Your IP: [::mailip::getip]"]
        ::smtp::sendmessage $msg \
                -header [list Subject "IP-Service"] \
                -header [list From "$::mailip::SENDER"] \
                -header [list To "$to"] \
                -servers $::mailip::SMTPSERVER
        ::mime::finalize $msg

 package provide mailip 0.1

tb: I added a valid sender to the namespace variables. It's needed, to let the Smarthost accept the outgoing email.